^ 
312. Minerals from New Holland. 
of curved lamine ; and the mineral sometimes pre- 
sents compound. varieties, consisting of lesser indi- 
viduals, flattened or compressed, so as to show only 
portions of their planes, or sections of smaller crystals, 
which have been prevented, by their mutual contact, 
from assuming their full and perfect proportions. 
These are united by similar parts, so as to have their 
similar faces in parallel position with each other. 
The surfaces of several of the larger crystals are free 
from. these. combinations, having bright, polished 
planes, measurable by the common goniometer: | The 
amygdaloid to which they are attached, abounds in 
vesicular cavities, some of which are filled by green 
earth and Ws nodules of chalcedony. 
D Fr cad Heulandite. | (Hemi-prismatic 
Fig. d. — . Kouphone-spar, M.) — The indi- 
: , viduals of this species present the - 
primary form, replaced on the ob- 
tuse solid angles by very minute 
I scalene, triangular planes, resem- 
bling om bahjéined Fig. 5, and being usually of 
nearly the same size. Color, pure white ; lustre of P, 
pearly ; secondary planes a, f, vitreous; but the 
faces M, T, possess a dull, waxy, or opalescent lus- 
tre, which I have not before observed in the crystals 
of this mineral, apparently, however, confined to the 
surface; and the same faces are more or less curved 
ity present replacements of iius planes upon the solid angles, as in 
the case of Analcime ; a modification which I do not find mentioned 
as having been before observed in the crystals of this species. I in- 
tend, eerie time, to refer again to this beautiful mineral, in 
connexi ith some other facts e while on a short bt to 
Nova c during the last summer. : 
