MINERALOCICAL NOTES. 
63 
VI.— Steatite (Talc.) 
This mineral occurs in crystalline limestone, or rather dolomite, 
at Harakgama, Pata Hewaheta, Central Province, both in rounded 
and ovoid masses less than an inch in diameter, resembling amyg- 
dules, and also in small hexagonal prismatic crystals with good 
basal cleavage, pearly lustre, &c., but terminating irregularly 
(unlike the rather similar individuals of phlogopite mica in which 
the basal plane is always well developed). Appearances suggest 
a secondary origin for the steatite. 
VII.— Stilbite. 
A rock specimen obtained from Nilhene graphite mine (near 
Baddegama) some 5 or 6 years ago was covered with small bright 
transparent crystals. These were examined by Mr. L. J. Spencer, 
M.A., and found to be stilbite, presenting the forms c (001), b (010), 
f (101), and m (110), and twinned like Dana’s figure 3. Stilbite has 
not previously been recorded from Ceylon. 
VIII.— Serendibite.* 
This rare mineral, hitherto only known from the moonstone 
pits at Gangapitiya, Dumbara, Central Province, is found also in 
the pits at Attaragala near the 11th milepost on the Katugastota- 
Teldeniya road. The occurrence here is similar to that origi¬ 
nally described ; the pits are distant from those at Gangapitiya 
nearly four miles, along the same line of strike. 
IX.— Moonstone. 
The following is an analysis of Ceylon moonstone (orthoclase 
felspar) from Gangapitiya, Dumbara, Central Province, made at 
the Imperial Institute. The material analyzed was clear, colour¬ 
less, and free from inclusions. The composition is that of an 
orthoclase rather rich in soda.f 
Si O., 
... 65-70 
H 2 O (combined) .. 
0-28 
ai 2 0 3 
... 19-85 
H 2 O (moisture) 
0-10 
Fe 2 O s 
0-17 
— 
Na 0 O 
... 520 
99-34 
K 2 O 
8-04 
— 
Mim. Mag., vol. XIII., 
No. 61, 1903. 
f It is noteworthy that the analyses of Ceylon orthoclase quoted in Hintze 1 
mineralogy show no soda. The said analyses are. however, quite old. 
