5 
the information of American mineralogists. The following extracts from 
Schaller’s paper will facilitate the description of the Canadian phosphorite. 
The French phosphorites are of three types: (1) holoerystailine, fibrous: (2) amor- 
phous (isotropic), homogeneous; (3) mixture of the amorphous and holoerystailine. 
(1) The holoerystallme, fibrous type is composed of either dahllite or francolite. 
Dahllite is a hydrous carbonate and phosphate of lime (free from fluorine), francolite and 
staffelite are considered by Lacroix to be identical, but the name staffelite is kept for the 
fibrous variety of francolite. Damour’s hydroapatite also is francolite. Francolite is 
similar to dahllite in composition, but contains notable amounts of fluorine. 
(2) The amorphous, perfectly isotropic type is composed of the mineral collophanite, 
which is a hydrous carbonate and phosphate of lime, generally free from any appreciable 
amount of fluorine, but rarely containing a small amount (fluocollophanite). 
(3) The third type is composed of the following minerals, in varying amounts: 
(a) Dahllite; (b) francolite (var. staffelite): (c) an unknown mineral, similar to 
dahllite and francolite in chemical composition, but differing optically from them; (d) 
collophanite. 
This type of phosphorite, composed of an amorphous mineral and one or more 
crystalline minerals, is called quercyite. If the unknown mineral ((c) above) is absent, 
the subtype is called a — quercyite; if the unknown mineral is present, the subtype is 
called p — quercyite. Quercyite is in many cases formed of alternating layers of a — 
quercyite and of 0 — quercyite. 
The Lake Francois phosphorite is unlike anything that has yet been 
described. It is essentially an association of quercyite and collinsite, a new 
mineral which was named after W. H. Collins, Director of the Geological 
Survey, Canada. A characteristic specimen containing both minerals 
is illustrated in Figure 1. The three layers A, B, and D are' quercyite. 
They are of variable width and where narrowest have a somewhat wavy 
structure in addition to their general botryoidal curvature. They are 
characterized by their dark brown colour and by having a cryptocrystalline 
appearance. The layer C represents collinsite. This mineral is very 
prominent and can be easily distinguished from quercyite by its lighter 
colour and coarser crystallization. 
COLLINSITE, A NEW MINERAL 
The collinsite layers consist of a medium brown mass of elongated 
blades having their axis approximately perpendicular to the surfaces of the 
layers. The blades vary in size from 1 centimetre in length by ^ milli- 
metre in width, to those of microscopic dimensions, and are not grouped 
with any particular optical orientation. The blades of collinsite are light 
brown and somewhat translucent, with a silky lustre. The specific gravity 
is 2-95 and the hardness is 3*5. Before the blowpipe the mineral fuses, 
with intumescence, at 3 into a brownish slag. It is easily soluble in acid 
and gives a strong reaction for water in the closed tube. Since quercyite 
decrepitates and does not fuse before a blowpipe, collinsite may be easily 
distinguished from it by a simple fusibility test. 
Optical Properties 
The collinsite blades lack crystallographic forms and in order to deter- 
mine the relationships between the optical and the crystallographic ele- 
ments, the writer employed the Fedoroff method as revised by Nikitin, 
using the universal stage on a microscope specially designed for the purpose. 
