several inches in diameter and of rich color, showing blue opalescence, at Morin, Que.
The
beautiful variety of albite called peristerite, exhibiting a peculiar
bluish chatoyancy or opalescence, is sometimes mingled with pale green
and yellow, and called " moonstone." It is found in crystals and in
large cleavable masses, containing disseminated grains of quartz, in
veins cutting the Laurentian strata at Bath-urst, Ont., on the north
side of Stony Lake, near the mouth of Eel Creek; in Burleigh, Ont., in
crystals, in large, opalescent, cleavable masses of reddish albite, and
north of Perth, Ont. It is also reported by Mr. G. Christian Hoffmann,
of the Canadian Geological Survey, in specimens showing beautiful blue
color, from Villeneuve, Ottawa County, Que.
Perthite
occurs in large cleavable masses in thick pegmatite veins, cutting the
Laurentian strata, and is often made up of flesh-red and reddish-brown
bands of orthoclase and albite, interlami-nated. When cut in certain
directions, it shows beautiful golden reflections like aventurine, and
being susceptible of a high polish, is adapted for an ornamental stone
or for use in jewelry. It is also found in considerable quantity at
Burgess, Ont, about seven miles southwest of the town of Perth, and
likewise near Little Adams Lake.
Sunstone,
aventurine feldspar, has been described by Dr. Bigsby in the form of a
largely crystallized flesh-red feldspar, constituting part of a
granitic vein traversing gneiss, twenty miles east of the French River,
on the northeast shore of Lake Huron, and occurs in fine specimens at
Sebastopol, Ont.
Obsidian
has been found in British Columbia, but it has little value except for
the cheaper jewelry, and even then is rarely used for such purposes.
The
porphyries which cut the Laurentian limestones in the townships of
Grenville and Chatham, Que., form a dike running east and west twenty
feet in breadth. They have a dark-green or brownish-black base,
homogeneous and compact, containing crystals of red orthoclase, and
admitting of a high polish, which strongly recommends the material for
ornamental use.
The pegmatite at Montgomery's Clearing on Allumette Lake, five miles above Pembroke, Ont., consisting of a brownish-
