APPENDIX 
To the report of the 2d Geological District containing 
descriptions of two minerals supposed to be new. 
Chiltmite? 
Colour white and greenish white. Structure foliated or cleavage, 
distinct in one direction; planes curved and imperfect. Primary forml 
Lustre, on the cleavage surface, pearly; on the face of fracture vitre- 
ous or semi- vitreous. Translucent — transparent. Fracture uneven. 
Cohesion strong. Hardness = 6, sp. gr. 2.892. 
Chemical characters, — Before the blow-pipe, in the outer flame, it 
instantly swells and becomes opake or milk white; in the inner, fuses 
readily into a blebby glass. With borax it fuses with intumescence in- 
to a colourless glass, and with salt of phosphorus into a slightly opaline 
or nebulous glass. In the flame of a candle or spirit lamp, a fragment 
becomes milk white and fuses on the corners and edges into a blebbley 
glass. Heated in a glass tube, it gives off water; it dissolves partially 
in muriatic acid, but does not form a jelly. From the muriatic solution 
oxalate and carbonate of ammonia throw down precipitates. 
Observations. — The above described mineral I found in West Port, 
Essex county, embedded in the hypersthene rock, in small quantities. 
It resembles Prhenite in its external characters in part, or it has a gene- 
ral resemblance to it, but is sufficiently distinct to constitute a distinct 
species. It also resembles the family of feldspars, but it is evident it 
cannot be a species of that mineral. In the natural system it belongs 
rather to the family of kouphone spars than feldspar, or it might very 
properly be placed between those two families, immediately after Prhe- 
nite. I have not been able to procure but one distinct cleavage. Its 
primary form is therefore unknown. In chemical composition it is also 
allied to the kouphone spars, being unquestionably a hydrous silicate of 
alumina and lime. 
