Calcite

Massive variety often dyed green to imitate jadeite. Chelsea: commonly red. Solvent test. May be impregnated with wax or plastic: hot point test - Blue Chart Gem Identification, Herve Nicolas Lazzarelli, 2010, p 9 3Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references 2.67 to 2.73Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references PerfectHerve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) Perfect and easyMore from other references ConchoidalArthur Thomas, Gemstones (2009) 1.486 to 1.658Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references Uniaxial/-Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references 0.172Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) DoublingMore from other references NilArthur Thomas, Gemstones (2009) e ray-0.008 to o ray-0.017Arthur Thomas, Gemstones (2009) White, yellowish, pink, bluish, orange, colourlessUlrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references Pink, CO2+W. William Hanneman, Pragmatic Spectroscopy For Gemologists (2011) Transparent,Translucent,OpaqueUlrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references Vitreous,ResinousArthur Thomas, Gemstones (2009) Inert to strong reaction, commonly pinkish-redHerve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) TrigonalHerve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references Scalenohedrons, rhombohedrons, stalactiteArthur Thomas, Gemstones (2009) A major rock-forming mineral. It occurs in limestones, marbles, chalks, a common cement in clastic sedimentary rocks, and as gangue in hydrothermal veins; in alkalic to mafic igneous rocks; common as speleothems in caves.Anthony et al, Handbook of Mineralogy (2001) Calcite information at mindat.org Colombia  DR Congo  [var: Cobalt-bearing Calcite] [var: Cobalt-bearing Calcite] Iceland  mindat.org Myanmar  Ted Themelis (2008) Gems & mines of Mogok Ted Themelis (2008) Gems & mines of Mogok Ted Themelis (2008) Gems & mines of Mogok Peru