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CHAPTER X
GARNET
GARNET
is a noun that is applied to a variety of gem minerals red or
brownish-red. Almandite, a stone of rich cherry, claret, or blood-red
colour is the precious garnet. A variety of garnet recently established
that is in high favour is rhodolite. The chemical bases of both of
these leading varieties are the same, a silicate of iron and aluminium.
Precious garnet has a hardness of about 7.5, with a specific gravity
seldom less than 4. and occasionally as high as 4.3. Closely following
almandite, or as jewellers call it, " almandine," in the favour of gem
fanciers, is Bohemian garnet or pyrope, meaning " fire-like "; this has
a range of colour from a deep blood red to almost black. Pyrope is
slightly harder than almandite, and its specific gravity lies between
3.7 and 3.8. The fracture is brittle; refraction, single; lustre,
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