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Equivalent ounce is an investing term used throughout the mining industry. For example, miners that primarily focus on gold might use gold equivalent ounce (GEO), silver miners often use silver equivalent ounce, and copper miners would likely focus on copper equivalent ounces. All of these variations on the term equivalent ounce are meant to do the same thing, create an equal footing across a miner's portfolio so investors can more easily evaluate production.
In nature gold and most other metals are rarely found by themselves. So, for example, when a gold miner builds a mine it is often producing metals like silver and copper along with the gold. However, if the miner is specifically focused on finding gold, the byproduct metals can make it hard for investors to get a clear picture of the company's current production profile compared against historical production and when making comparisons to other miners.
To simplify things, a gold miner with byproduct metals in its portfolio will often provide both gold ounces produced and gold equivalent ounces produced to show what the byproducts would add to production if they were hypothetically sold and used to buy gold. As noted above, this isn't unique to gold. Many metals are found together in nature. And depending on a miner's focus, some commodities may end up being tangential to the company's business. Using equivalent ounces makes it easier for investors to get a handle on production without the need to consider multiple metals.
The resulting figure from either of these equations can then be added to the company's gold production to create an overall GEO figure for the company. Companies will usually provide the prices used in the above equations, since the current spot price for a given metal will most likely be different from the one used to create the financial report or news release at which you are looking. If not, then a conversion ratio will normally be provided, which is simply the gold price divided by the byproduct price in the second equation above.
Some miners even calculate multiple variations if their production is split roughly evenly between two metals or if they are attempting to shift their focus from one metal to another over time. So, for example, a miner with a 50/50 split between silver and gold production might provide both a silver equivalent ounces metric and gold equivalent ounces. The silver equivalent ounces metric will effectively assume that all of the company's gold production is sold and the proceeds are used to buy silver. The gold equivalent ounces production will do the opposite.
Let's do a little math to see how the equations work. Assume a miner produces 500 ounces of gold and 15,000 ounces of silver. The gold price for the period is $1,250 an ounce and the silver price is $15 an ounce. The math looks like this:
Every miner has a slightly different production profile based on the mines they operate. By providing equivalent ounces, companies are attempting to make comparisons between different companies and different reporting periods easier. Essentially, by using GEOs you can compare like to like, and not have to complicate the picture with copper and silver that aren't a primary part of a gold miner's goals or production. The same is true for the other equivalent ounce variations.
Gold equivalent ounce, or the other variations, make it easier for investors to make comparisons. However, it's still important to remember that each commodity has its own supply and demand dynamics that drive prices.
For example, most gold demand stems from the jewelry and investment spaces, while silver and copper see significant demand from industrial sources. These variations can have a material impact on the prices of the metals over time. Copper tends to rise in price when economic growth is strong, as demand for products that use copper (like wires and pipes) increases. Gold, on the other hand, is seen as a store of wealth when times are tough. It tends to do relatively well when the markets are facing turbulent times, like during economic contractions that might push the price of copper lower.
Simply put, the current prices and price trends for the byproduct metals can have a material impact on how much they contribute to the overall GEOs figure. This doesn't negate the value of using GEOs, but it is something that investors should keep in mind as they look at a miner's financial reports.
In the end, gold equivalent ounces (or other equivalent ounce variations) allow investors to more easily compare a company's production to its own history and to the production of industry peers. The numbers will vary over time depending on commodity prices of the byproduct metals, but that's a relatively modest concern compared to the value provided by the GEO figures. Now that you have a better handle on this metric you'll have another tool at your disposal when evaluating the quarterly reports from the miners in your portfolio.
When most people hear borax they think about laundry. But at Manhattan Gold & Silver, we think about gold refining. Thats because this mineral does more than wash clothes its an important flux in metallurgy for separating gold from slag.
Youve probably seen borax in the detergent aisle, but it has several uses spanning multiple industries. Not only is borax a detergent, but its also used to make water softeners, buffering agents, anti-fungal products and much more. It also plays an important role during the gold refining process as a flux.
In metal refining, a flux is sort of like a cleaning agent because it helps remove impurities from a sample. With some borax, heat, and a little know-how, its possible to extract pure gold from a sample of ore. This is because using borax as the flux reduces the melting point of all the elements in a piece of ore, including gold.
While out in the field, a gold prospector can grind and wash a piece of ore, then mix it with borax in a plastic bag. The bag is then placed in a bowl or crucible and heated. The heating action is what triggers the borax to go to work. Once the borax melts, it lowers the melting temperatures of everything in the ore. As all of the minerals melt down, they separate from one another. As the process continues, the borax causes the other minerals to oxidize and breakdown even further. Gold is unaffected by this reaction and sinks to the bottom of the mixture, intact.
The mixture of oxidized impurities and flux becomes slag, which is scraped away to reveal the pure gold at the bottom of the crucible. Because borax is so cheap and effective at extracting gold, borax-based refining techniques were very popular during the 19th century gold rushes. It still continues today among individual prospectors and small-scale mining operations.
Be it gold, copper, cobalt or uranium, the African continent has powerful resources for mining. And there are several industry-friendly governments that are ready to secure their futures with new projects.
African Gold Group(TSXV: AGG; US-OTC: AGGFF) has set its sights on building Africas next mid-tier gold producer. A definitive feasibility study was filed in July 2020 for its 100%-owned Kobada gold project in Mali. Developing the project would require a capital expenditure of $125 million, plus an $11 million contingency.
The study forecast the post-tax net present value at a 5% discount rate would be C$266 million with an internal rate of return of 41.1% at a gold price of $1,530 per ounce. The mine would produce 100,000 oz. gold per year for the first five years and a total of 728,654 oz. over a 9.4-year mine life. Over the life of the mine, all-in sustaining costs would be $784 per oz. gold.
African Gold is currently updating the definitive feasibility study to add tonnage to reserves and expand resources. The company says considerable work will also be done to optimize mining and scheduling, refine the mineral processing flowsheet and engineering a larger tailings containment facility. Such work will support the mining of sulphide resources and their treatment in a carbon-in-leach (CIL) plant.
Cobalt Blockchain(TSXV: COBC; US-OTC: COBCF) plans to supply ethically sourced cobalt from the Democratic Republic of the Congo (DRC). The company and its partners have developed a blockchain-based certification method called Mintrax that will be piloted on its own operations.
The company has two joint ventures totaling more than 48-sq-km in the DRC. It has a 70% interest (private partner 30%) in the operator Alpha Cobalt SAS about 50 km east of Kolwezi and 10 km from the Tenke Fungurume copper-cobalt mine, which is owned by China Molybdenum and a private Chinese equity firm. Cobalt Blockchain also holds an 80% interest in Cobalt Blockchain SAS with another private partner. These holdings cover two concessions in an area 50 km from Lubumbashi with active artisanal and small scale copper-cobalt mining.
In preparation for launching its Mintrax technology, perhaps as early as May this year, Cobalt Blockchain has strengthened its management team, created a special advisory committee, and settled its outstanding debt.
In January 2021 an updated preliminary economic assessment was done for a bio-heap leaching project. The initial capital cost would be C$341 million to create a mine and mill that would treat 55,000 tonnes of ore per day over a 24-year mine life. With copper recovery at 85%, Haib would produce 2.2 billion lb. copper equivalent over its life. A lower mining rate would significantly reduce the capex requirement, the company says.
Deep-South has examined the project at four different copper prices producing widely varying economic scenarios. At a copper price of $2.25 per lb., the project has an after tax net present value (NPV) at a 7.5% discount rate of $439 million and an after tax internal rate of return (IRR) of 18.9%. At $3.00 per lb. copper, the after tax NPV jumps to $957 million, and the IRR to 29.7%.
The company says it has so far only scratched the surface of the 370-sq-km property, but has already outlined 3.1 billion lb. of copper in indicated resources (in 456.9 million tonnes at 0.31% copper) and 2.2 billion lb. in inferred resources (342.4 million tonnes grading 0.29% copper).
The porphyry deposit contains a 140 million tonne high grade zone with grades of between 0.5% and 1.0% copper in widths of up to 150 metres. The company says the high grade zone is expected to grow as infill drilling proceeds to determine a measured resource. The zone is open to the east and west with potential for two additional open pits.
Ethiopia and Tanzania are the focus forEast Africa Metals(TSXV: EAM; US-OTC: EFRMF) where the company has three advanced projects. In Ethiopia the companys 70%-owned Harvest and 100%-owned Adyabo copper and gold projects have mining licences and in Tanzania East Africa Metals 100%-owned Handeni project is a pure gold play.
The most advanced of these projects is Adyabo, where two mines the Malo Bula pit and underground and the Da Tambuk open pit are shovel-ready. Construction has been delayed until the Ethiopian government lifts its covid-19 travel bans. There will be a year of construction at both mines, according to the company, and together they are forecast to be mined at a rate to 300,000 tonnes per year.
The mill can be built in phases. The first will have a gravity-flotation flowsheet with anticipated recoveries of 70% for gold and 85% for copper. In the third year of operation, a carbon-in-leach (CIL) plant will be built to increase gold recovery to 90%, the company says.
At the Handeni property, a reprocessing operation for tailings from the artisanal Magambazi gold mine was commissioned earlier this year. The operator, PMM Mining, plans to produce 10,000 oz. gold in the first year of operation and 20,000 oz. in the second. Thirty percent of the output will be sold to East Africa at the price of production plus 15% with third party smelting, refining, transportation and royalties minus by-product credits.
At the Harvest property, East Africa has prepared a preliminary economic assessment for the Terakimti heap leach project in 2018. The study outlined a post-tax net present value of $13.2 million at an 8% discount rate and an internal rate of return of 30.1%. The Terakimti oxide resource has 1.1 million indicated tonnes grading 3.20 grams gold per tonne, 23.60 grams silver per tonne, and 0.08% copper. There are also 15,000 inferred tonnes grading 1.94 grams gold, 13.50 grams silver, and 0.04% copper.
The primary sulphide resource, recoverable first by open pit and then underground methods, contains 1.8 million tonnes grading 1.06 grams gold, 17.50 grams silver, 2.20% copper and 1.65% zinc. The open pit portion contains 2.6 million inferred tonnes grading 0.96 grams gold, 20.60 grams silver, 1.09% copper and 1.42% zinc; and the underground resource is 939,000 inferred tonnes at 0.84 grams gold, 15.20 grams silver, 0.69% copper, and 2.92% zinc. The property lies in the highly prospective Asmara mineral belt.
Readers who followEndeavour Mining(TSX: EDV; US-OTC: EDVMF) will know it as West Africas No.1 gold producer with 2020 output of 1.5 million oz. from eight mines: Hound (90% ownership), Boungou (90%), Mana (90%), Karma (90%), and Wahngion (90%) mines in Burkina Faso; the Sabodala-Massawa (90%) in Senegal; and the Ity mine in Cte dIvoire (85%). These producing mines are all solid performers that are increasing ore production and have exploration for future growth.
Endeavour is also pursuing a number of greenfield opportunities, the most advanced being the Fetekro (80%) gold project in Cte dIvoire. The prefeasibility study has been updated this year for a multi-million-ounce project. The latest update also proposes doubling the mill capacity, a change that would boost production by 76% to 209,000 oz. annually. A solar hybrid power plant is also planned.
Endeavour puts Fetekros proven and possible reserves at 31.9 million tonnes grading 2.07 grams gold. A three million-tonne per year plant would operate with that material for 9.5 years. A definitive feasibility study is due by the end of 2021.
The Kalana (80%) gold project has the potential to produce 150,000 oz. per year, according to the company. The reserve estimate was updated earlier this year to proven and probable reserve of 35.6 million tonnes grading 1.6 grams gold per tonne for 1.8 million oz. gold, enough to support a mine life of 11 years. Endeavour expects to complete a definitive feasibility study on Kalana in the first quarter of 2022.
Endeavours pipeline for future production holds a great deal of promise. Endeavour has earlier stage exploration projects in Burkina Faso (Bautou and Nabanga) and Cte dIvoire (Afema and, with Barrick Gold, Sissedougou-Mankono). It has additional exploration properties in Mali, Guinea, Niger and another in Burkina Faso.
Global Atomics (TSX: GLO; US-OTC: GLATF) flagship asset is the Dasa uranium project in Niger. The environmental impact statement has been submitted and approved and a mining permit was issued in December 2020. The current exploration permits have been extended until the end of 2023.
The Dasa deposit is sandstone hosted with several horizons ranging from Jurassic to Carboniferous in age. There are low levels of deleterious elements such as molybdenum or vanadium. Uranium recovery is expected to be well above 90%, the company says.
According to the preliminary economic assessment prepared a year ago, first phase of production would see the establishment of a mine with a 12-year life that would produce 44.1 million lb. uranium oxide (U3O8) with an average processed grade of 5,396 parts per million. Based on a uranium price of $35 per lb., the after-tax net present value at an 8% discount rate would be C$211 million for an after-tax internal rate of return of 26.6%. Estimated cash costs are $16.72 per lb. U3O8 and an all-in sustaining cost of $18.39 per lb. U3O8.
Global Atomic went to Process Research Ortec to pilot metallurgical tests in Canada last year. Samples representative of what will be treated during the first 20 months of mining were treated. Uranium oxide recovery was 92.8% after leaching during the first campaign, according to the company. The second campaign using samples representative of deeper ore, reached a recovery rate of 97.8%, and the third campaign with reduced use of acid recovered between 95.1% and 94.1% uranium.
Solvent extraction based on sodium carbonate stripping technology combined with a uranyl peroxide precipitation process resulted in near quantitative conversion of uranium from the leach into final yellow cake product, Global Atomic reported. The yellowcake was dried or calcined to produce UO4 or U3O8, respectively.
Global Atomic also holds a 49% stake in Befesa Silvermet in Turkey. The joint venture recovers zinc concentrate by recycling aluminum slag and steel dust. The companys share of production during 2020 was $1.0 million.
Namibia Critical Metals(TSXV: NMI; US-OTC: NMREF) first set its sights on Namibia in 2005 when it began exploring the Lofdal rare earth oxides (REOs) project, 450 km northwest of Windhoek. The project is interesting for its dysprosium and terbium mineralization as well as large amounts of yttrium.
In 2018, the company acquired a 95% interest in seven critical metals properties in the mountainous southeastern part of the country. A strategic partnership was struck with the former owner, Gecko Critical Metals (Pty), and shares issued to Gecko, making it the major shareholder of Namibia.
The Lofdal project is the most advanced of the companys holdings. A 43-101 resource estimate was completed in 2012. The deposit contains 2.9 million indicated tonnes grading 0.08% light REOs and 0.24% heavy REOs. There are 9,234 contained tonnes of REOs with HREO enrichment of 76.3%. The inferred material totals 3.9 million tonnes at 0.07 light REOs and 0.20% heavy REOs. This portion contains 8,973 tonnes of REOs with HREO enrichment of 74.7%.
A preliminary economic assessment was completed in 2014 for a mine and processing plant that would have an annual production of 1,500 tonnes of separate REOs. While soft rare earth prices have meant the project is not moving forward quickly, Namibia says there is potential to expand the current resources with more drilling.
The companys Epembe tantalum-niobium property in the northern part of the country covers a well-defined, very large multi-phase carbonatite dyke that has been mapped and surface sampled along 10 km 7 km of which is mineralized. The carbonatite contains variable amounts of pyrochlore, which is enriched with tantalum. There is also phosphate present. Only 15% of the dyke has been drilled with concentrations of 150 parts per million tantalum pentoxide, 1,300 ppm niobium pentoxide and 2.4% phosphate. Namibia intends to advance the project to the preliminary economic assessment stage.
Its Kunene cobalt-copper project is a new discovery in the northern part of Namibia. It covers an area of favourable stratigraphy along strike west of the Opuwo deposit belonging to Celcius Resources. The company plans to test several extensions of the dolomitic ore formation for sediment hosted cobalt and copper, orogenic copper and stratabound zinc-lead mineralization. Most of the occurrences, the company says, are likely related to what has been termed the Streilrand hydrothermal system. There are a number of historic copper-cobalt targets that have not previously been tested for cobalt to follow up.
In addition, the company has three other early stage projects in the country the Grootfontein nickel-copper-lead-zinc-vanadium-gold property, the Otjiwarongo rare earths and gold property, and the Erongo gold project. Airborne surveys have been flown over Grootfontein and Otjiwarongo, but Erongo has not been systematically explored.
Newcore Gold(TSXV: NCAU; US-OTC: NCAUF) is focusing its near-term energies on its 100%-owned Enchi gold project in Ghana, Africas number one gold producer. The deposits lie along one of West Africas most prolific and developed gold trends, the Bibiani gold belt. The Enchi project covers 216 sq. km along 40 km of the prolific Bibiani Shear zone, the setting of some of Ghanas most successful mines. Enchi lies in the Sefwi-Bibiani belt and Kinross Golds Chirano mine is about 50 km to the north.
The Enchi property covers several gold occurrences, including the known zones of Boin, Sewum and Nyam. Gold grades near the surface tend to be low, and drilling has only averaged 50 metres to date. No holes have been drilled to more than 200 metres. All the gold zones are open at depth.
In August 2020, an 8,000-metre reverse circulation (RC) drill program was started.The results and those of drilling done in 2017-18 allowed the company to file a 43-101-compliant report in October 2020, which outlined 1.2 million oz. of gold in the inferred category in 52.9 million tonnes grading 0.72 gram gold per tonne. The resource estimate used a cut-off grade of 0.30 gram gold per tonne.
The company has chosen several high priority gold targets that could expand the near surface oxide resources. As part of the expanded program, drilling this year will test extensions of defined deposits,retest previous holes that had no significant mineralization, and complete first pass drilling of anomalous zones on a 1-km-scale.
On April 28, Newcore increased its 2020-21 drill program to 66,000 metres, including an additional 8,000 metres of RC drilling. It also reported some recent assays from its Kojina Hill gold target, with highlights of 59 metres of 0.79 grams gold per tonne from 61 metres downhole, including 10 metres of 3.03 grams gold over 10 metres from 80 metres.
Other work planned for this year includes metallurgical testing, geotechnical assessments, and a detailed topographic survey. Existing anomalies and targets will also be trenched and sampled geochemically.
Silver has long been valued for its white metallic lustre, its ability to be readily worked, and its resistance to the corrosive effects of moisture and oxygen. The lustre of the pure metal is due to its electron configuration, which results in its reflecting all electromagnetic radiation of wavelengths longer than 3000 angstroms (3000 angstroms is in the ultraviolet range). Thus, all visible light (that is, light with wavelengths between 4000 and 7000 angstroms) is effectively reflected, conferring the white colour.
Silver (Ag), like gold, crystallizes in the face-centred cubic system. It melts when heated to 962 C (1,764 F). With a density of 10.49 grams per cubic centimetre, it is the lightest of the precious metals. It is also the least noble of the precious metals, reacting readily with many common reagents such as nitric acid and sulfuric acid. Metallic silver can be dissolved from gold alloys of less than 30 percent gold by boiling with 30-percent-strength nitric acid in a process referred to as parting. Boiling with concentrated sulfuric acid to separate silver and gold is called affination. Both these processes are used on a commercial scale for separating silver and gold.
Silver was discovered after gold and copper about 4000 bce, when it was used in jewelry and as a medium of exchange. The earliest known workings of significant size were those of the pre-Hittites of Cappadocia in eastern Anatolia. Silver is generally found in the combined state in nature, usually in copper or lead mineralization, and by 2000 bce mining and smelting of silver-bearing lead ores was under way. Lead ores were smelted to obtain an impure lead-silver alloy, which was then fire refined by cupellation. The best-known of the ancient mines were located at the Laurium silver-lead deposit in Greece; this was actively mined from 500 bce to 100 ce. Spanish mines were also a major source.
By the 16th century, Spanish conquistadores had discovered and developed silver mines in Mexico, Bolivia, and Peru. These New World mines, much richer in silver, resulted in the rise of South and Central America as the largest silver-producing areas in the world. For the recovery of New World silver, the Patio process was employed. Silver-bearing ore was ground and then mixed with salt, roasted copper ore, and mercury. The mixing was accomplished by tethering mules to a central post on a paved patio (hence the name of the process) and compelling them to walk in a circle through the mixture. The silver was gradually converted to the elemental state in a very finely divided form, from which it was dissolved by the mercury. Periodically, the mercury was collected and distilled to recover the silver, and this was subsequently refined by cupellation. Cyanidation processes supplanted the Patio process in the late 19th century; by that time, the Moebius and Thum Balbach electrorefining processes had been introduced.
In the mid-19th century a large silver deposit was discovered in Nevada. This resulted in the United States becoming the worlds largest silver producer until the 20th century, when it was surpassed by Mexico and South America (particularly Peru). By the early 21st century, Mexico, China, Peru, Australia, and Russia had become the worlds leading silver producers.
Although some silver-bearing ores contain silver as their largest metal value, virtually none has silver as its main constituent. A typical ore might contain 0.085 percent silver, 0.5 percent lead, 0.5 percent copper, and 0.3 percent antimony. After flotation separation, the concentrate would contain 1.7 percent silver, 10 to 15 percent lead, 10 to 15 percent copper, and 6 percent antimony. Approximately 25 percent of the silver produced comes from ores actually mined for their silver value; the other 75 percent comes from ores that have as their major metal value either lead, copper, or zinc. All these ore minerals are sulfides; typically, lead is present as galena (PbS), zinc as sphalerite (ZnS), and copper as chalcopyrite (CuFeS2). In addition, the mineralization usually includes large amounts of pyrite (FeS2) and arsenopyrite (FeAsS). The silver mineralization is usually argentite (Ag2S), proustite (Ag3AsS3), and polybasite [(Ag,Cu)16Sb2S11].
Silver-bearing ores are mined by open-pit or underground methods and then are crushed and ground. Since virtually all the ores are sulfides, they are amenable to flotation separation, by which a 30- to 40-fold concentration of mineral values is usually achieved. Of the three major types of mineralization, lead concentrates contain the most silver and zinc concentrates the least.
The smelting and converting of copper sulfide concentrates result in a blister copper that contains 97 to 99 percent of the silver present in the original concentrate. Upon electrolytic refining of the copper, insoluble impurities, called slimes, gradually accumulate at the bottom of the refining tank. These contain the silver originally present in the concentrate but at a much higher concentration; for example, a silver content of 0.2 percent in the sulfide concentrate can result in a slime containing 20 percent silver. This is smelted in a small furnace to oxidize virtually all metals present except silver, gold, and platinum-group metals. The metal recovered, called dor, generally contains 0.5 to 5 percent gold, 0.1 to 1 percent platinum metals, and the balance silver. This metal is cast to form anodes and electrolyzed in a solution of silver-copper nitrate. Two different electrorefining techniques are employed, the Moebius and Thum Balbach systems. The chief difference between them is that the electrodes are disposed vertically in the Moebius system and horizontally in the Thum Balbach system. The silver obtained by electrolysis usually has a purity of three-nines fine; on occasion it may be four-nines fine, or 99.99 percent silver.
Lead concentrates are first roasted and then smelted to produce a lead bullion from which impurities such as antimony, arsenic, tin, and silver must be removed. Silver is removed by the Parkes process, which consists of adding zinc to the molten lead bullion. Zinc reacts rapidly and completely with gold and silver, forming very insoluble compounds that float to the top of the bullion. These are skimmed off and their zinc content recovered by vacuum retorting. The remaining lead-gold-silver residue is treated by cupellation, a process in which the residue is heated to a high temperature (about 800 C, or 1,450 F) under strongly oxidizing conditions. The noble silver and gold remain in the elemental form, while the lead oxidizes and is removed. The gold and silver alloy thus produced is refined by the Moebius or Thum Balbach process. The residue from silver refining is treated by affination or parting to concentrate the gold content, which is refined by the Wohlwill process.
Zinc concentrates are roasted and then leached with sulfuric acid to dissolve their zinc content, leaving a residue that contains lead, silver, and goldalong with 5 to 10 percent of the zinc content of the concentrates. This is processed by slag fuming, a process whereby the residue is melted to form a slag through which powdered coal or coke is blown along with air. The zinc is reduced to the metallic form and is vaporized from the slag, while the lead is converted to the metallic form and dissolves the silver and gold. This lead bullion is periodically collected and sent to lead refining, as described above.
Approximately 60 percent of all silver produced is used in the photographic industry, and the metal can be recycled from spent photographic processing solutions and photographic film. The solutions are processed on-site electrolytically, while film is burned and the ashes leached to extract the silver content.
High-grade jewelry scrap is usually realloyed on-site rather than being refined. Jewelry sweeps, the fine dust generated in the polishing and grinding of precious metals, are usually smelted to form an impure silver, which is electrorefined. Because of the much lower value of silver scrap, recycling techniques applicable to gold (e.g., cyanidation of low-grade scrap) are uneconomic for silver. Low-grade silver scrap is instead returned to a smelter for processing.
The fire assaying techniques described above for gold are equally applicable to silver. In order to determine the silver content of a fire assay bead, the bead is first weighed, then boiled with 35-percent-strength nitric acid to dissolve its silver content, and then weighed again. The weight loss defines the silver content, and the remaining residue contains the gold. In order to ensure complete dissolution of the silver, the silver content of the bead should be at least 6070 percent. A process routinely employed in the fire assaying of gold ores is the addition of silver prior to fusion of the ore in order to ensure that the silver content of the final bead is high enough to dissolve. This is called inquartation, and the separating of silver and gold by leaching with nitric acid is referred to as parting.
911MPE hassmall gold mining equipment for sale andmore specifically mineral processing equipment. Our equipment is best used in small scale extractive metallurgyoperations operated by small miners or hobbyist prospectors and mining fanatics. 911MPE offers gold mining equipment as well as processing equipment applicable to most any base metals: copper, lead, zinc, nickel, tin, tungsten and more. For the relatively small size of equipment offered, sample preparation and metallurgical laboratories can economically buy good alternatives to the usually unaffordable equipment for sale in the classic market place.
911MPE has for target market what mining professionals consider the pilot-plant scale mining operation or artisanal mining operations with a focus around under 500TPD. Metals you can extract include: gold, silver or other of the precious group as well as the classic base metals; copper, lead, zinc, nickel, molybdenum. Much of our ultra-small scale equipment allows you to process from just a few kilo (pounds) per day and work on your passion for a small budget.
You can buy from us mineral processing equipment starting from crushing, grinding, classification, dredging, gravity separation, flotation, pumps, water treatment and smelting. A line of ovens, furnaces and laboratory equipment is also available.
Making a complete list of gold mining equipment starts with defining the type of gold mining you are doing and the budget you have at your disposal. The type of mining relates to hard rock,eluvial, or placer; alluvial deposits. The capital budget you have to invest in buying your equipment with dictate the scale at which you want to mine and influence the long-term operating costs of your mining operation.
Since most of the information online provides lists of gold mining equipment for amateur level mining with equipment like: gold pans, metal detectors, mini sluice box, blue bowl, geologist rock pick, soil scoop, hand screens/classifiers. The items listed just now fall closer to gold prospecting tools and equipment than actual mining.
I will present here what I consider are major equipment lists for 3 types of mining operations. Remember now, a metallurgist is writing. This will not be flawless and since my speciality is process equipment, that is mostly what will be discussed.
Some amateur level gold prospecting equipment such as metal detectors are often classified as mining equipment by small miners/prospectors operating as a hobby. These items include but are not limited to:Get in Touch with Mechanic