1894.] Mineralogy. 597 
MINERALOGY.’ 
Contributions to Swedish Mineralogy, Part I:—In this 
paper Sjögren? has given in English a very interesting series of crys- 
tallographical studies. The well known but rare axinite from Nord- 
marken is reexamined. In addition to the tabular crystals described 
by Hisinger and v. Rath’s prismatic type, a third type of smaller 
erystals is identified having neither the tabular nor the prismatic hab- 
its and highly modified. —Hedyphane which is closely related chemi- 
cally to the members of the apatite group, particularly mimetite, has 
been supposed to possess monoclinic symmetry on the basis of Des 
Cloiseaux’s determination in 1881.  Sjógren has examined crystals 
from the Harstigen mine in Wermland and finds that both crystallo- 
graphically and optically hedyphane is hexagonal. The crystals 
examined exhibited the forms oP, o» P, P, 4P, 2P, P2, 2P2, and clear- 
ly belong to the apatite group. Another member of the apatite group 
is discovered in Sjégren’s new mineral svabite, which occurs in scheffer- 
ite at the Harstigen mine. Svabite is a hydrous calcium arsenate of 
the composition indicated by the formula HO Ca, As, O,, in which the 
hydroxyl appears to be part replaced by chlorine and fluorine. The 
mineral is crystallographically like apatite and exhibits the forms 
æ P, P, P2, oP. Thesame mineral was found at Jacobsberg, enclosed 
in hausmannite. A very exhaustive study is made of the minerals of 
the humite group, all of which are found at Nordmarken. No less 
than 29 forms were observed on chondrodite from this locality, and 
these include the six new forms, + 3P,—1P,--1P,—i P3,+ P2, — 5 Pi. 
The humite of the locality showed 20 and the clinohumite 26 forms, all 
of which have been observed on Vesuvian crystals. A probable 
fourth member of the humite group which occurs at Nordmarken, is 
announced in this paper. Three new analyses of longbanite are con- 
tributed, on the basis of which the formula of the mineral is given as 
m Sb,O, n Fe, O, p R'"R"O, in which R'—Mn and Si, and R"—Mn, Ca, 
and Mg. Thesymmetry of the mineral is shown to be rhombohedral, this 
and the chemical constitution indicating its isomorphous relation with 
hematite and ilmenite. Adelite is the name given to a new basic 
arseniate from Nordmarken, Jacobsberg and Longban, having the for- 
1Edited by Dr. Wm. H. Hobbs, University of Wisconsin, Madison, Wis. 
Bull. of the Geol. Inst. of Upsala, I; No. 1, (1892), pp. 1-64, pls. I-IV. 
