Horn silver is the common name for cerargyrite (chlorargyrite), a halide mineral composed of silver chloride (AgCl). The name comes from its horn-like appearance after weathering and polishing by wind and dust. Horn silver is real silver ore containing approximately 75% pure silver and 25% chlorine. It forms as a secondary mineral in oxidized zones … Read more

Silver 500, also called “Half Silver,” is a silver alloy containing 50% silver and 50% copper. It was commonly used in British coins from 1920-1946 and occasionally in jewelry where cost is a concern. Silver 500 isn’t magnetic (it’s diamagnetic) but is allergenic due to its copper content. This makes it unsuitable for people with … Read more

Ruthenium is hypoallergenic and one of the least likely jewelry metals to cause allergic reactions. This means ruthenium isn’t toxic in its solid form as used in jewelry. However, while ruthenium is hypoallergenic, it’s often alloyed with allergenic metals which then make it allergenic. Ruthenium is also used to thinly coat allergenic base metals (like … Read more

Silver 875 is a silver alloy containing 87.5% pure silver and 12.5% other metals, typically copper. It was historically used in Russia and Eastern Europe and was called “84 Zolotnik Silver” from the Russian purity system where 84/96 zolotniks equals 87.5% silver. This silver alloy is non-magnetic and generally hypoallergenic, though copper sensitivity happen occasionally. … Read more

Iridium is hypoallergenic and is one of the precious metals least likely to cause allergic reactions. However, while iridium is hypoallergenic, it can still be alloyed with allergenic metals which would then cause problems for people with metal allergies. For example, there’s known cases of people reacting to iridium in Platinum Iridium (900 Plat – … Read more

Osmium is hypoallergenic and is one of the least likely jewelry metals to cause allergic reactions. However, this only applies to osmium in solid state (osmium jewelry and osmium bullion). Osmium in powdered form oxidizes and forms osmium tetroxide, a highly toxic and corrosive substance which causes severe burns and irritation to the skin, eyes, … Read more