No. 1628. ON METHORIC OHROMITES—TASSIN. 687 
size most of them being a millimeter or more in diameter. No 
rounded grains or minute particles were noted. The crystals were 
commonly in distorted and occasionally twinned octahedrons. These 
twins were usually simple, once only were striations noted which 
would lead to the belief that polysynthetic twinning had occurred. 
Color, blue-black; luster, brilhant; nonmagnetic. Composition: 
CC Es (2 Frei eet a a ee nel ee sac et Mey inten ee Be eI ane a pe ae 61. 39 
PANS Ch epee SOc ees BUS oe Bera etn age atch pe kie Natee HPO 6 
TE OO) Pie Le ees oir Eat UN oC a ea one ei gitsnces. SOV AG 
NE: ©) Sater Se 2) f sg I eee i even ncp ae SO AU) 
THE HENDERSONVILLE METEORITE. 
Chromite occurs very sparingly in portions of the stone as dissemi- 
nated dust-like, nonmagnetic particles. The mineral showed no evi- 
dences of crystallization and was blackish-brown in color with a dull 
resinous luster. Composition : | 
CSTIGay C) lap ae ine ks Ne tee ihe oy STON ar rg eS 56. 73 
AS © sect mua ene ee ae en iG EN SEY OC Da 298 
IE) © Ges Sine oa irre suas | Ss ut pe MAE ay ay gta arent a 29. 64 
MgO____ Se MRR SEN ah i ee Ss SIE Wess rar ele se ee 2.42 
THE PERSIMMON CREEK METEORITE. 
Chromite occurs sparingly associated with carbon and olivine in 
certain troilite areas. No crystals were noted, the mineral occurring 
in dull black nonmagnetic grains. Not enough material was secured 
for quantitative work and its identity was established by the blow 
plpe. 
CASAS GRANDES METEORITE. 
Chromite occurs very sparingly in this iron as minute rounded 
erains, which under the microscope were decidedly greenish blue in 
color. The material was strongly magnetic. Because of the very 
small amount separated it was not possible to do more than prove 
the presence of chromium by the bead test. 
CANYON DIABLO METEORITE. 
Out of the numerous fragments examined but two contained min- 
erals of the chromite group. In one case it was associated with 
troilite and silicon compounds in areas rich in carbon. Here the 
chromite occurred as rounded grains having a blue-black color and 
a dull luster. It was strongly magnetic and had the following 
composition : 
OTs Og eso is oie eae eae ont Eee rm 5. 20 
Fe.O3 ~------~ -- ee 65. 25 
HC OuSi ee saree ae be Lea aaa ees ares 2 Lo BO), OS) 
