MGS wouldn’t be in business if it weren’t for the incredibly hardworking gold miners who keep the worldwide supply of gold and precious metals going. Since the early North American gold rushes, the mining industry has developing a jargon all its own. Here are some of our favorite terms non-miners are unlikely to know.
Color – visible gold that usually appears in loose dirt or processed material. Miners will usually shout something along the lines of “This sluice box is showing some color!”
Fool’s gold – iron sulfide with a roughly 50/50 construction of iron and sulfur. Also known as pyrite. It looks a lot like gold, and may fool inexperienced prospectors or miners.
Mother Lode – what every gold miner is searching for: a major vein or dig site that is rich with gold
Gangue – the opposite of “color;” worthless rocks, minerals, and other material that needs to be separated from gold.
Giant powder – a miner’s term for dynamite, probably because of the giant sound and explosion it creates.
Gumbo – fine-grained soil that becomes sticky and waxy when wet. In water-based mining operations, gumbo can be a real pain-in-the-neck.
Quicksilver – liquid mercury. Formerly an important ingredient for removing gold from ore. It's used less and less in modern times because of its toxicity. Borax is now a preferred material for extracting gold from ore, rather than quicksilver.
Tommy-Knocker – the ghost of a miner who knocks on the rocks and underground structures. Not to be confused with a regular Knocker – a mythical sprite-creature whose name comes from the knocking on mine walls that occurs right before cave-ins. Both noises are actually caused by creaking timber and underground support structures.
From 1896 through the 1930s, the Gorham Manufacturing Company produced a limited line of silver hollowware known as martelé (derived from the French verb marteler, "to hammer”). Even though ostentatious silverware isn’t in style anymore, we imagine some of our pawnbroker clients would be ecstatic if a martelé item came into their shop.
While martelé work has high precious metal content (.95% silver, comparable to Britannia silver), its true value comes from the incredible skill and patience that went into each piece – which wouldn’t have been possible without using high-purity silver as a base.
As any jeweler would tell you, impurities are added to precious metals to toughen them up (in most cases). By using 950-fine silver instead of 925-fine sterling silver, martelé craftsman have easier material to work with – which matters a lot in the martelé process. As the name implies, each piece was hammered and chased completely by hand. Even something as small as an ornate pepper shaker took as long as 25 hours to produce, with an additional 25 hours for chasing.
It is estimated that about 4,800 martelé pieces were produced. But, after silver’s price spike in the 1980s, many pieces were melted down, leaving about 1,500-1,700 known pieces. If you do manage to get your hands on some martelé, you’d likely be better off keeping it, rather than recycling it.
In a previous blog post, we discussed Argentium silver alloys and how they use the addition of germanium to impart a number of beneficial properties to the silver. One particularly noteworthy property was the elimination of firescale.
Firescale, (or as they say in London, firestain) is a dark discoloration caused by heating. It’s a cosmetic problem that can a real pain-in-the-neck for jewelry craftsman. The only way to fix an unsightly firescale is to either buff it off with acids or abrasives, remove the affected silver, or plate over it with a fresh layer of silver.
The reason why silver alloys are vulnerable to firescale is because of their copper content. As the silver is heated, it allows oxygen molecules to pass through. This causes the copper to oxidize well below the surface – creating firescale that is difficult to remove. However, germanium can prevent firescale because it oxidizes preferentially to the copper. Furthermore, germanium oxide is transparent.
When Argentium silver is heated, the germanium oxidizes creating a transparent layer that protects the copper in the alloy from oxygen exposure. Without that exposure, copper oxide never forms and firescale never appears. Since germanium oxide is self-regenerating, the alloy is permanently protected from firescale – making it a superior coating compared to rhodium, which will wear away eventually.