A significant new find of demantoid and andradite took place in Namibia in 1996 at what is now dubbed the " Green Dragon " mine.
12.
Like the other garnets, andradite crystallizes in the cubic space group Iad, with unit-cell parameter of 12.051 ?at 100 K.
13.
In 1849, Nordenskjold examined what was known as " Ural's chrysolite " and discovered that it was a rich green variety of andradite garnet.
14.
The different species are pyrope, almandine, spessartine, grossular ( varieties of which are hessonite or cinnamon-stone and tsavorite ), uvarovite and andradite.
15.
Two calcium-rich members of the garnet group fare much better : these are grossularite ( usually brownish orange, rarely colorless, yellow, green, or pink ) and andradite.
16.
Both grossular and andradite are isotropic and have relatively high RIs ( ca . 1.74 and 1.89, respectively ) and high dispersions ( 0.027 and 0.057 ), with demantoid's exceeding diamond.
17.
The ugrandite garnets have Ca 2 + in the X position : uvarovite ( Ca 3 Cr 2 ( SiO 4 ) 3 ), grossular ( Ca 3 Al 2 ( SiO 4 ) 3 ) and andradite ( Ca 3 Fe 2 ( SiO 4 ) 3 ).
18.
Minerals encountered in xenoliths include : andradite, anhydrite, anorthite, apatite, biotite, calcite, diopside, fassaite, garnet, gypsum, ilmenite, magnetite, monazite, orthopyroxene, perovskite, plagioclase, prehnite, quartz, sphene, thorite, wilkeite, wollastonite and zircon.
