lighter
than crystallised quartz. The hardness of crypto-crystalline quartz is
6.5; specific gravity, 2.6; it is more difficult to break than
crystalline quartz, being very tough, which makes these
varieties—their principal differences being of colour and
colour-pattern—eminently fit for carving.
The
finest moss agates known to-day come from India, and those specimens
called " mocha stone " originally came, it is believed, from the
vicinity of Mocha, an Arabian seaport at the entrance of the Red Sea
most famous for its aromatic coffee. The Oriental moss agates are
common in the volcanic rocks (trap rock) of western India, occurring
with Mocha stone. Blocks weighing as high as thirty pounds have been
obtained. It occurs also as pebbles in many Indian rivers. From China
has come, during recent years, a supply of natural green and artificial
yellow and red moss agates, which have, to a considerable extent,
replaced others on the market. Fine moss agates are abundant in various
parts of the Rocky Mountains; the best are found in the form of rolled
pebbles in the beds of streams. As souvenirs, and for sentimental
reasons of local interest, these
beautiful gem stones of our Rocky Mountain
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