Archive for the Gemstones Category

Spinel

Spinel is actually a Magnesium Aluminum Oxide mineral which can be also used for gemstone purposes. It is commonly found colored red, green, blue, purple, brown, and black but red is by far the more common color. Spinel is usually found showing vitreous luster in reflected light of polarizing microscopes…

Brazilianite

Brazilianite is a Sodium Aluminum Phosphate Hydroxide mineral. It is commonly found colored yellow to greenish yellow and colorless. Most commonly found more fascinating under polarizing microscopes used in the field of optical mineralogy. Brazilianite is also commonly found exhibiting a vitreous luster in reflected light of polarizing microscopes used…

Sinhalite

Sinhalite is actually a Magnesium Aluminum Borate mineral. Most crystals of mineral Sinhalite are found transparent to translucent in appearance. Sinhalite is known to crystallize in the orthorhombic system of crystal formation. The crystal habits of mineral Sinhalite are quite limited to alluvial grains found in gem gravels which can…

Taaffeite

Taaffeite is actually a Beryllium Magnesium Aluminum Oxide mineral. It is commonly found exhibiting vitreous to adamantine luster in reflected light of polarizing microscopes. Most crystals are commonly found transparent to translucent in appearance. Taaffeite is usually found crystallizing in the hexagonal system of crystal formation. The crystal habit of…

Moissanite

Moissanite is known as Silicon Carbide mineral.  Moissanite is most commonly found green thouh it may be nearly colorless to essentially black sometimes. Moissanite is also found showing adamantine luster when viewed closely under polarizing microscopes used in the field of optical mineralogy. Crystals of mineral Moissanite are usually found…

Periclase

Periclase is actually a Magnesium Oxide mineral. It is usually found exhibiting vitreous to adamantine luster when evaluated in reflected light of polarizing microscopes. Most crystals of mineral Periclase are found transparent to translucent in appearance. Periclase is known to crystallize in the isometric system of crystal formation. The crystal…

Rhodochrosite

Rhodochrosite is actually a Manganese Carbonate mineral. This can be used for jewelries. It is commonly found showing interesting colors like red to pink, sometimes almost white, yellow and brown. When evaluated in reflected light of petrographic polarizing microscopes, Rhodochrosite is usually found exhibiting vitreous to resinous luster. Most crystals…

Turquoise

Turquoise is actually a Hydrated Copper Aluminum Phosphate mineral. It is most commonly used as gemstone. This gem mineral is most commonly found colored turquoise, but this color actually varies from greenish blue to sky blue shades. When closely evaluated in reflected light of polarizing microscopes for mineralogists, Turquoise is…

Andalusite

Andalusite is actually an Aluminum Silicate mineral. But this can be used for gemstone purposes. The crystal habit Andalusite is commonly includes prismatic crystals with a square cross section terminated by a pinacoid which can be found more clearly visible under polarizing microscopes used in gemology as well as in…

Malachite

Malachite is actually a Copper Carbonate Hydroxide mineral. Commonly used as jewelry. This gem mineral is usually found showing color of banded light and dark green or just dark green if in crystalline form. Malachite is also most commonly found showing dull luster in massive forms and silky when found…