A few images shot at our shop on GIA open house day. Once a year we have GIA students in through their alumni programs. The top picture shows the actual smelting of pure gold. Next is a shot of the gold being mixed with the alloy to make it into 18kt white gold. The next shot is that gold being vacuum cast. At bottom the raw 18kt white gold castings. The advantage of hydrogen for silver, gold and platinum is incredibly clean heat. 5000+ degrees Fahrenheit. Since hydrogen is an element as is oxygen, there is no carbon in the combustion as with natural gas, propane and acetylene. This illustrates how clean our environment could be if our primary fuel were hydrogen. The byproduct is pure water. One great precious metal that responds badly to hydrogen is palladium and palladium white gold.
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