Smaltite: Cobalt Diarsenide. Arsenic 72%, Cobalt 28%. This mineral, an important ore of Cobalt, occurs in crystals and in masses; is tin-white to steel-gray in color and a
good conductor of electricity. It is especially abundant at Cobalt,
Ontario.
Smithsonite: Zinc
Carbonate. Zinc Protoxide 65%, Carbon Dioxide 35%. It occurs in druses,
masses, granular aggregates, but rarely crystallized. Color white,
grayish, greenish, brownish-white, and sometimes blue.. When colored
orange, by greenockite, it is called "Turkey-Fat Ore."
This
mineral is an important ore of Zinc, and was named after James
Smithson, the founder of the Smithonian Institute of Washington.
A translucent green variety, with a bluish tinge, found at Laur-ium, Greece, is employed for ornamental purposes.
Smoky Quartz:
(also called Cairngorn) : a transparent, smoky-brown colored Quartz.
The profusion of these stones at Cairngorn, Scotland, led to their
adoption as a sort of national gem, and brilliants of considerable
size were set in swords, buckles, brooches, etc.
Soapstone: (see Steatite).
Sodalite: Silica
37%, Alumina 31%, Soda 26%. A mineral so-called from the large
proportion of soda it contains. It occurs crystallized or massive, and
is of a bluish-green color. This stone resembles Lapis Lazuli in color,
but is a little less brilliant. It occurs in Italy, Norway, and
Hungary; also in Montana and Maine. The specimens from Maine are used
as an ornamental stone.
Spessartite: Manganese-Aluminium Garnet. A dark hyacinth-red variety of Garnet, and is used as a gem stone.
Sphalerite: Zinc
Sulphate Zinc 67%, Sulphur 33%. One of the most important zinc ores,
and one of the most interesting of minerals from a crystallographic
standpoint. It is often called "zinc blende," and the dark colored
varieties are sometimes called "Black Jack" by the miners. It occurs in
crystalline masses, in handsome crystals and crystal groups, color
yellow, brown, black; also red, green to white. Transparent to
translucent. Crystallized Sphalerite is found abundantly at Alston
Moor, England; at various places in Saxony; in Switzerland; and in New
South Wales. The principal deposits in America are those in Iowa,
Wisconsin, Missouri Kansas, Colorado and Idaho.
