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be very irregular in form and to vary considerably in 
size, tlie largest attaining a width of about 2 ’2 5 mm. and 
the smallest about 075 mm. They exhibited no distinct 
crystalline form, but a peculiar indented appearance was 
observed on the surfaces of some individuals, whilst others 
were pebblelike, somewhat convex and rounded off as though 
they had been mechanically acted upon by water. The quartz 
grains did not exhibit the slightest trace of crystalline form 
but were rounded off and pebble-like. Both the garnets 
and the quartz grains could be extracted from the matrix, 
a cast of their forms being left behind. The red grains 
fused easily and quietly before the blowpipe to a black 
bead, which was not however magnetic ; they were some- 
what attacked by hydrochloric acid with a slight separation 
of powdery silica : the presence of iron was also detected. 
The hardness of the mineral was 7'5, and its specific- 
gravity 4’09 at 9°C. I hope shortly to determine the 
chemical composition. A microscopical examination of 
the garnet grains showed them to be crystalline, exhibiting 
certain marked peculiarities, and after a careful examina- 
tion of many of them I came to the conclusion that the 
form in which they crystallised was the rhombicdodeca- 
hedron. I had previously proved them to be crystals 
of the regular system by examining the grains in polarised 
light and finding them to be isotropic. The crystals were 
built up out of myriads of minute laminated abnormal 
rhombicdodecahedrons, two faces of which have been enor- 
mously developed at the expense of the other faces. 
These laminae are arranged parallel with each other in posi- 
