Adularia (Moonstone) is a semi-precious, clear, transparent, glassy form of potashfeldspar which is found mainly in the crevices of crystalline schists and gneisses, often in beautifully perfect crystals. It has sometimes a pearly, opalescent reflection or play of colours. It derives its name from Adula, a mountain peak in Switzerland, where fine specimens are found. Research Adularia
Asteria is the name applied to a variety of corundum, which displays an opalescentstar of six rays of light when cut with certain precautions. The name is also applied to the cat's-eye, which consists of quartz, and is found especially in Sri Lanka. Research Asteria
Jasper is an opaque, cryptocrystalline variety of quartz that takes a high polish and is used as a gemstone. It is usually stained by impurities and occurs in various colours, such as red, green, yellow, and blue. When the colours are arranged in bands, the mineral is called riband jasper; a variety containing alternating bands of red and green is known as Siberian jasper. Mottled yellow or brown varieties of jasper are called Egyptian jasper. Agate jasper is intermediate in structure between true jasper and chalcedony . Inclusions of red jasper occur in heliotrope. The jasper mentioned in the Bible as one of the stones in the breastplate of the high priest and as the foundation of the wall of the New Jerusalem is believed to have been a dark green, opalescent stone. The jasper of the ancients was a partially translucent stone, probably containing some chalcedony and a variety of the latter known as chrysoprase. Research Jasper