59- Peridot of Ceylon.
60. Chrysoberyl, the true cat's eye—an ordinary kind of cat's-eye is quartz
when cut en cabochon.
61. Pleonaste, a kind of spinel.
62.
Zircon, very abundant 'in Ceylon, crystallizes in the terragonal
system; disregarded by the Sinhalese except the white variety which is
cut and sold as Matura-diamond; often however, Matura-diamonds are rock
crystal.
63. moon-stone, a pearly variety of felspar, quartz, and selenite are often cut and sold as moonstone.
64. Steatite or soapstone, a massive variety of.
65. Quartz (teruwana).
66. Quartz (crystal) palingu.
67. Refuse stone.
68. Gem sand.
69. Unassorted gem stones.
70. Gem sand from Pelawatta, Kalutara,
71. Cinnamon Garden sand.
72. Cabook gravel from Colombo.
GEOLOGY AND MINERALOGY.
(From Ferguson's "Summary of Information regarding Ceylon")
The
Geological formations met with in Ceylon are of the Palaeozoic,
Mezozoic and recent age. The greatest portion of the island consists of
ancient sedimentary beds, doubtful deposited sea or lake, metamorphoses
have obliterated all traces of fossil remains. Mountain ranges formed
of primary and metamorphic rock. Principal rock, gneiss, with beds of
laterite (locally named " cabook") and dolomite, according to some
authorities,—described by others as crystalline marble or primary
limestone. Plenty of iron, but no trace of coal. Manganese. Gold and
platinum, but in such small quantities not apparently worth gathering.
Molybdenum, Cobalt, Nickel, Tin, Copper and Arsenic also occur.
Plumbago, the only mineral of commercial importance. Cretaceous beds of
Jaffna of Mezozoic age. Nitre in caves. Salt forms naturally, and is
also manufactured in sufficient quantity at Puttalam, Jaffna, and
Hambantota, to supply the consumption of the Island. Calcareous Tufa
met with at Bintenne deposited from warm springs. Hot springs at
Trincomalee and other places, but no direct evidence of present
volcanic action, and earthquakes seldom perceptible. Greenstone,
however, underlies gneiss at Kadu-gannawa, and with vitrefactions is
observed in fissures of rocks at Trincomalee. Spring of Sulphurretted
Hydrogen similar to Harrowgate water occurs in Puttalam district. Large
tracts of alluvium occur in the Nuwara Eliya and other districts.
Process of slow upheaval believed to be in operation on western coast,
with compensating disintegration of mountain ranges. Recent formation a
breccia formed of particles disintegrated rock held together by
calcareous and ferruginous matter near Negombo and along coast. Gems
abundant especially about Ratnapura (" city of gems") but, with
exception of blue sapphire and ruby, of slight value. A flawless
sapphire is rare and good rubies are excessively scarce. Zircon or "
Matara-diamond," and amethyst, common. Chrysoberyl (or " cat's-eye,")
not uncommon, curious, and often prized. Moonstones (very beautiful
form of " adularia ") and " cinnamon stones," (brown garnets) common.
Spinel and tourmaline very abundant. Many rocks and river beds sparkle
with red garnets, beautiful but intrinsically valueless, Ceylon is
celebrated for fine pearls.
