500 Transactions.— Geology. 
rapidly, accompanied by a singing sound; falls to pieces, and becomes 
translucent on the thin edges; breaks with a conchoidal fracture ; adheres 
strongly to the tongue; yields to the thumb nail and affords a shining 
streak ; possesses an earthy smell. 
Schrétterite ? —Malvern Hills. (Labelled “ Pinite.’’) 
In rounded wax-like masses, filling the cavities of an amygdaloidal 
trachyte (?) rock, and as a mammillated incrustation upon its surface; 
green, grey, and white; hardness about 9:5; streak white, rather tough; 
breaks into more or less conchoidal flakes; translucent; waxy lustre. 
Before the blow-pipe it becomes white and opaque, and much harder (thus 
differing from the ordinary behaviour of both pinite and allophane), intu- 
mesces slightly, and tinges the flame green ; affords deep blue when ignited 
with cobalt nitrate; does not gelatinize with hydrochloric acid, but granular 
silica is thrown down ; gives off much water when heated in closed tubes. 
ZEOLITES.* 
Natrolite.—Sunnyside, Dunedin. 
In radiated tufts of white acicular crystals, and coating a hemispherical 
concretion of ferruginous calcite. 
Presented by Mr. D. Millar. 
Natrolite. 
In beautiful radiated tufts of acicular crystals. 
Natrolite.—Dunedin. 
Natrolite.—Dunedin. 
Natrolite.—Dunedin. 
Associated with an incrustation of siderite or iron carbonate. 
Natrolite.—Dunedin. 
Compact form, exhibiting radiate structure; lining amygdaloidal cavi- 
ties in basalt. 
Natrolite, —Dunedin. 
Forming a thin investing eoating on interior of amygdaloidal cavity. 
Stilbite ? —Dunedin. 
In the cavities of these specimens are minute detached crystals of one 
of the zeolites. The form appears to be that of the rhombic prism capped 
with the pyramid; this is a combination often assumed by stilbite, and in 
addition the little crystals possess a very high lustre, not unlike that of 
stilbite; moreover, they behave like that mineral before the blow-pipe, hence 
they probably belong to the same species. 
Not sufficient to permit an analysis to be made without destroying the 
specimens completely. 
* Rep. N.Z. Exh., 1865, p. 438. 
