dae JOURNAL OF THE 
mineral. This is analogous to the composition of the al- 
bite—anorthite feldspars. 
The approximate ratios deduced from the above analy- 
ses,of SiO, : Al,O, :(Ca.Na,)O°: LO =4.: 1: l= See 
give for the formula of this chabazite wz: 2, but with a 
low amount of water. 
The variation in and the high specific gravity of the 
mineral is without doubt due to the varying proportions 
of barium and strontium in the molecule. 
The occurence of the chabazite at Buck Creek is in- 
teresting as being the only known locality of this miner- 
al in North Carolina. 
ANORTHITE.”* 
The occurrence of this feldspar at Buck Creek, Clay 
Co., N. C., has been described by J. V. Lewis.** The 
mineral forms with olivine a mass of forellenstin (trocto- 
lite) rock, outcropping over an area of about two acres, 
at the extreme eastern border of the peridotite outcrop. 
The particles of feldspar vary in size from that of a pea 
to some nodules that were an inch anda half long by 
three-quarters of an inch broad and are separated from 
the olivine by a zone of fibrous silicates, composed partly 
of enstatite. 
The two cleavages are well developed in all the spec- 
imens of the mineral and in many of these the striations 
on the basal cleavage are very distinct. 
The feldspar has suffered some kaolinization but the 
interior of the larger nodules is apparently free from all 
decomposition. By means of the heavy solution a pro- 
duct was obtained for analysis that varied in specific 
gravity from 2°0995 to 2°7440. 
*Am. J. Sci. Vol.; ¥,,.1998,, p. . Vas. 
**N. C. Geological Survey, Bulletin 11, p. 24. 
