520 A POPULAR EXPOSITION OF THE 
33-2, zirconia 668. The transparent, yellowish-red 
A varieties are employed in.jewellery under the name of 
rey Hyacinth. Small crystals, sometimes of good quality, 
CZ: occur in the erystalline limestone (Laurentian Series) 
of Grenville township, Argenteuil Co., C. E. Those 
Fig. 33. Which have come under our observation are simply in- 
teresting as mineral specimens, but Sir William Logan has obtained 
some of fine colour and transparency, “ constituting veritable gems.” 
(Esquisse géologique du Canada.) 
Andalusite.—Chiefly grey or pale red; in granular masses, and in 
rectangular or rhombic prisms. The latter are sometimes compound, 
presenting a cruciform figure on the cross section. These constitute 
the variety Chiastolite, (fig. 34.) H. (normally) = 2 ii: 
7-0-7°5, but often less by alteration or weathering ; ij: 2= 
sp. gr. 3°1-3°2. Quite infusible. General composi- = 
tion: silica 37, alumina 68. In Canada, this mineral Fig. 34. 
occurs in reddish erystals and small masses in micaceous schists 
(altered Silurian strata,) around Lake St. Francis in the counties of 
Megantic and Beauce. It may be distmguished from feldspar by 
its higher specific gravity, and also by its complete infusibility. 
Staurolite:—Brown, red, greyish. ©Gommonly in cruciform 
(Trimetric) crystals; otherwise in more or less simple, rhombic 
prisms. H 7-7°5, but sometimes less by alteration ; sp. gr. 3 5—3°8. 
Quite infusible. General composition: silica, alumina, peroxide of 
iron. This mineral occurs sparingly in the metamorphic strata of 
the Eastern townships, although it is abundant in the mica slate of 
Maine, Vermont, &c. 
Rutile :—In small crystalline scales and grains, and in flattened 
square-based prism-pyramids, of a red or orange colour, with semi- 
metallic lustre. H. 6:0-6°5; sp. gr. 4°15-4°25. Infusible. Forming 
with borax in a reducing flame a dark amethystine-blue glass, which 
by exposure to an intermittent flame, becomes transformed into a 
light-blue enamel. In Canada, Rutile, in a distinct form, occurs only 
in small quantities in the iron-ores of the Eastern metamorphic 
region, as in the townships of Sutton, Bolton and Brome ; and with 
ilmenite in the Laurentian rocks of Baie St. Paul, Canada East. It 
consists of Titanic acid (= Oxygen 39, Titanium 61.) 
Condrodite :—Chiefly in small granular masses of a deep yellow 
