M. Godon’s mineralogical observations. 133. 
monly white, with a shade somewhat greasy, but preserving, almost 
always, its laminary texture. [Menotomy ©, Waltham ©}. The 
external part of this rock, long exposed to the air, presents the fels- 
par in a state of decomposition ;. but, when fresh broken, it shows 
great compactness, and even lustre. It is susceptible of a good pol- 
ish, and may be considered as perfectly analogous to the black gran- 
ite of the ancients, (granito nero, of the Italians). 1 think proper to 
give it the name of granitic amphiboloid. 
7. The two elements, which compose the preceding species, are 
sometimes promiscuously blended together, in particles so fine and 
imperceptible, as hardly to permit the magnifying glass to evidence 
that it is a compound mineral. [Brookline O, Concord turnpike oJ]. 
This rock, which is an instance of the aggregation of two single min- 
erals in a kind of moleculary state, breaks commonly into acute an- 
gular fragments, sometimes prismatic. On account of the resem- 
blance of this aggregate with the Trapp of the Swedes, I give it the 
name of Trappine psi acige = 
8. Amphiboloid, : incaliactenticean eck collie 
cludes crystal and felspar, prescueindt white parallelopipeds imbedded 
in.a dark field. This variety, found contiguous to the preceding, 
[Lynn ©] is ranked under the generic title of amphiboloid, with the 
specific name of porphyritic. 
Porphyritic amphiboloid is tegen sats with sulphurated 
iron (common pyrites). 
9. A feature, which seems characteristic of the amphiboloid and 
felsparoid sof this country, is their being frequently intercepted by 
veins of a substance, generally of a compact texture, and of a green 
colour, of various degrees of intensity. The thickness of these veins: 
varies, from that of a shect of paper, to two, three, or more inches. 
The characters, derived from the external appearancc, and even those 
