Magnesite occurs as veins in and an alteration product of ultramafic rocks like serpentinite, turquoise and other magnesium rich rock types in both contact and regional metamorphic terranes. These Magnesites often are cryptocrystalline and contain silica as opal or chert. Magnesite is also present within the regolith above ultramafic rocks as a secondary carbonate within soil and subsoil, where it is deposited as a consequence of dissolution of magnesium-bearing minerals by carbon dioxide within groundwaters. Some of the best Magnesite deposits that can produce gemstone quality material are co-located with Turquoise deposits in the southwestern United States. Magnesite like Howlite, can be died to look like actual Turquoise.
Dichroic glass is glass containing multiple micro-layers of metal oxides which give the glass dichroic optical properties. The invention of dichroic glass is often erroneously attributed to NASA and its contractors, who developed it for use in dichroic filters. However, Dichroic glass dates back to at least the 4th century AD as seen in the Lycurgus cup. Dichroic glass is an example of thin-film optics.
Ivoryite is a great substitute for ivory. It is a sedimentary precipitate of magnesium, calcium and silica. It is 5 to 5-1/2 on the Moh's scale, which makes it slightly harder than ivory. Ivoryite can be worked with metal tools, but cuts effortlessly with diamond tools. Polishes well with diamond, tin oxide, cerium oxide or white rouge. Excellent material for inlay, cabochons and small carvings. Do not confuse Ivoryite with Ivorite, whic is a black tektite material from Africa. The majority of Ivoryite currenly comes from the western United States, especially Colorado and California.
Jasper, a form of Chalcedony, is an opaque, impure variety of silica, usually red, yellow, brown or green in color; and rarely blue. This mineral breaks with a smooth surface, and is used for ornamentation or as a gemstone, especially in jewelry. It can be highly polished and is used for vases, seals, and at one time for snuff boxes. When the colors are in stripes or bands, it is called striped or banded Jasper. Jaspilite is a banded iron formation rock that often has distinctive bands of Jasper. Jasper is basically Chert which owes its red color to iron inclusions. Peppermint Jasper is a named variety of brown, tan and white striped banded Jasper.
Crystals and cat-eye beads are also used in this set.
