ISO 9002 Concurrent
AuRIC's professional lab services meet the highest in quality standards.
An assay is an analysis of raw ore or refined metal to determine the presence, absence, or quantity of one or more components. Refined precious metals, like gold silver and platinum are assayed to test the purity of the metal.
Investment decisions are often determined by assay results. Because the stakes are so high, the reputation of the assayer is key to ensuring accurate analysis. AuRIC is recognized as a reputable leader in this important arena of metallurgy.
Fire and/or chemical analysis of ore samples are performed using the latest AA/GFAA/ICP techniques.
Assaying techniques are contantly improving. AuRIC's lab services are on the cutting edge of these technologies.
Analytical Protocol Development
Specializing in bringing solutions to refractory ore samples.
Laboratory, bench and pilot scale testing.
Due to its relative chemical inertness gold is usually found as the native metal or alloy. Occasionally large accumulations of native gold (also known as nuggets ) occur but usually gold occurs as minute grains. These grains occur between mineral grain boundaries or as inclusions within minerals. Common gold associations are quartz often as veins and sulfide minerals. The most common sulfide associations are pyrite, chalcopyrite, galena, sphalerite, arsenopyrite, stibnite and pyrrhotite. Rarer mineral associations are petzite, calaverite, sylvanite, muthmannite, nagyagite and krennerite.
Gold is widely distributed in the Earth's crust at a background level of 0.03 g /1000 kg (0.03 ppm by weight). Hydrothermal ore deposits of gold occur in metamorphic rocks and igneous rocks; alluvial deposits and placer deposits originate from these sources.
The primary source of gold is usually igneous rocks or surface concentrations. A deposit usually needs some form of secondary enrichment to form an economically viable ore deposit: either chemical or physical processes like erosion or solution or more generally metamorphism, which concentrates the gold in sulfide minerals or quartz. There are several primary deposit types, common ones are termed reef or vein. Primary deposits can be weathered and eroded, with most of the gold being transported into stream beds where it congregates with other heavy minerals to form placer deposits. In all these deposits the gold is in its native form. Another important ore type is in sedimentary black shale and limestone deposits containing finely disseminated gold and other platinum group metals.
Gold occurs in sea water at 0.1 to 2 mg / t (0.1 to 2 ppb by weight) depending on sample location.
Silver is found in native form, combined with sulfur, arsenic, antimony, or chlorine and in various ores such as argentite (Ag 2 S ) and horn silver (Ag Cl ). The principal sources of silver are copper, copper-nickel, gold, lead and lead-zinc ores obtained from Canada, Cobalt, Ontario, Mexico, Peru, Australia and the United States.
This metal is also produced during the electrolytic refining of copper. Commercial grade fine silver is at least 99.9% pure silver and purities greater than 99.999% are available. Mexico is the largest silver producer. According to the Secretary of Economics of Mexico, it produced 80,120,000 troy ounces (2492 metric tons ) in 2000, about 15% of the annual production of the world.
Platinum is often found free in areas of the Americas and alloyed with iridium as platiniridium. The platinum arsenide, sperrylite (PtAs 2 ), is a major source of platinum associated with nickel ores in the Sudbury Basin deposit near Ontario, Canada. The rare sulfide mineral cooperite, (Pt,Pd,Ni)S, contains platinum along with palladium and nickel. Cooperite occurs in the Merensky Reef within the Bushveld complex, Transvaal, South Africa.
Platinum, often accompanied by small amounts of other platinum family metals, occurs in alluvial placer deposits in the Witwatersrand of South Africa, Colombia, Ontario, the Ural Mountains, and in certain western American states.
Information used from Wikipedia.com for gold, silver and platinum.