NEW MINERAL OCCURRENCES. 
INESITE, 
SAN CAYETANO MINE NEAR VILLA CORONA, STATE OF DURANGO, MEXICO. 
MUSEUM No. M 5889. 
A specimen of inesite from the above locality was first secured 
by the writer in the spring of 1896 while at Villa Corona. Having 
later determined the mineral by its blowpipe characters as inesite, 
a request was sent to Mr, John D. Almy, one of the proprietors of 
the mine, to procure more specimens if possible. Through his 
kindness, and that of Mr. W. H. Schlemm, a few more specimens 
were obtained, and were generously placed at the writer’s disposal 
for study. The rarity of the mineral makes the find of interest, as 
it is known at only three other localities in the world, viz.: The 
manganese mines at Nanzenbach, northeast of Dillenburg, Ger- 
many; the Harstig mine, Pajsberg, Wermland, Sweden,* and 
Jakobsberg, Nordmark, Sweden.+ In the specimens from the San 
Cayetano mine the mineral occurs partly in cavities and partly in- 
tergrown with calcite and a flesh-colored manganesian calcite. 
These fill narrow veins in what is probably an altered andesite. 
The inesite occurs in tufts of radiating crystals which are of the 
characteristic flesh-red color. The most characteristic pyrognostic 
reaction of the mineral, noted by the writer, is, that when heated 
in the closed tube it becomes opaque, gives off water, and falls 
to powder. The crystals are of slender, prismatic habit, averaging 
about 5 mm. in length. None were found doubly terminated, the 
attachment at one end preventing the development of faces there. 
A total of seven forms was identified, as follows: 
a (100), 4 (010), ¢ (001), g (201), @ (ort), 
k (11.0.12), and s (946). : 
Of these the forms # (11.0.12) and s(g46) are new. The form & 
occurred on several crystals, the form s was found on but one. The 
*Dana’s Mineralogy, Sixth Edition, p. 564. 
+First Appendix to Dana’s Mineralogy, 1899. 
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