176 N. von Kokscharov on the Clinochlore of Achmatowsk. 
Arr. XVII.—On the Clinochlore of Achmatowsk ; by N. von 
Koxscuarov.* © 
Tue green mineral of Achmatowsk, remarkable for its dichro- 
ism and its perfect cleavage, was for a long while regarded as 
idence with the chlorite of Werner. Von Kobell} first re- 
ked the difference from that species of both the Achmatowsk 
aulevite and another of like characters from Schwarzenstein, and 
gave to them the name ripidolite (from gas, feather and dbo: 
from Westchester, Pa., has been described by W. P. Blake, 
as “Sahin which is not different from the Achmatowsk 
Speci 
The ‘crystals of Achmatowsk according to von Kobell are hex- 
agonal. All other mineralogists have adopted this view. At the 
suggestion of my esteemed instructor, G. Rose, I made in 1851 
many measurements of the crystals, and in my paper I also de- 
scribed it as hexagonal.f 
{The author here observes that his former measurements were 
made with great care with the reflective goniometer; and that 
although discrepancies with calculation were observed, and the 
planes were not always simple in their crystallographic signs, the 
habit of the crystals appeared to be hexagonal, and this view was 
hesitatingly adopted. He then proceeds, as follows. 
observations on my labors of G. Rose and M. Kenngott, 
and especially a letter from J. D. Dana giving a description of 
the Clinochlore and its analysis by Mr. Craw, led me to suspect 
pam the crystallization of the Achmatowsk chlorite was mono- 
clinic.§ 
As the Achmatowsk mineral has now proved to be monoclinic 
and its name has been the occasion of some perplexity in the 
science, I propose to retain the name Clinochlore for the species, 
including with it also the Schwarzenstein mineral; and I have 
consequently placed this name at the head of this article. 
Read before the Akademie der beter seci zu St. Petersburg, Sept. 20, 
ase and ep emg in bene xiii, of their Mem 
+ Jour. Chem., xvi, 4 839. 
¢ Ver fo der K. K. Min Ges, St. Petersb., 1850 and 1851, p. 163, and Pogg. 
Texxy, 5 
§ [The notes in the original ma ee 
a rom the letter of J. ek oe here omitted.—Ebs. ] 
