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PRECIOUS STONES.
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Lapland,
close to the Norwegian frontier, in a valley near Yaranger Fjord. The
whole district consists of gneiss traversed by bands of pegmatite, and
it was in sand derived from these rocks that the discovery was made. Of
the associated minerals, Velain gives (the most abundant coming first)
Garnet, Zircon, Hornblende, Glaucophane, Kyanite, green Augite, Quartz,
Corundum, Eutile, Magnetite, Stauro-lite, Andalusite, Tourmaline,
Epidote and Oligoclase felspar, and he believes the Diamond originated
in the pegmatite, and at the same time as that rock was formed.
It
is of interest to note that Professor Heddle obtained a specimen of
rock from three miles north-east of Ben Hope, in Sutherland, Scotland,
containing a "red Mica, red Zircons and either colourless Garnets or
Diamonds," and it is recorded in the "Mineralogy of Scotland," vol.
ii.,p. 194, by Mr. A. Thorns, that Dr. Heddle was confident, in his own
mind, from their optical properties, that these were Diamonds. The
point is of great interest, as beyond this there seems no record of
this mineral occurring in the British Islands. At Carratraca, in Spain,
Diamond is reported to have been found in a stream with Serpentine.
In
North America Diamonds have frequently been found since 1850, when the
first one was discovered in the alluvial workings for gold in
California. Since this time they have been found at intervals both in
the recent alluvium and also in the ancient detritus covered by lava
flows. The Californian localities include, in Amador Co., Volcano,
where an association with Garnet and Chalcedony is seen ; Fiddletown,
with Gold and lead- and copper-ores ; in Butte Co., the Cherokee ravine
with Zircon, Chromite, etc.; in El Dorado Co., at Forest Hill. In
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