Mine detail: Letterman Mine

Previously called 'Montana Premier Mine'

Location:	Sanders County, Montana, United States, North America
Lat / long:	47.42849, -114.89543
dep_id:	10019046
mrds_id:	DC08401
Commodity type:	metallic
Major mineral:	Gold
Minor mineral:	Lead, Silver
Trace mineral:	Copper
Operation type:	Unknown
Production size:	Small ammount of material produced
Development status:	Past Producer
ore:	Galena, Gold
gangue:	Quartz, Siderite
orebody_fm:	POD/LENS
ore_ctrl:	Fault Zone. The Opening Which Allowed The Placement Of The Ore Body Could Have Been Formed By Two Possible Ground Movements, A Reverse Fault Or A Stike-Slip Fault.
Reporter:	Unknown, Rojstaczer, Stuart A.
hrock_unit:	Prichard Formation
hrock_type:	Argillite
arock_unit:	Belt Series Intrusives
arock_type:	Diorite
Structure:	Broad Folds In The Argillites Which Strike About N., Fine Grained Dioritic Sill Is Exposed At The Adit Portal. Massive Fault, Six Ft Wide, Which Trends N 32 Deg W And Dips 72 Deg Sw.
tectonic:	Belt Basin
Year first produced:	1911
yr_lst_prd:	1940
discr:	Letterman
References:	Analytical Data:: SRC.REF: CROWLEY, F. A., 1963 , MONTANA BUREAU OF MINES AND GEOLOGY BULL. 34 , P. 26 Deposit:: MONT. BUREAU OF MINES & GEOL. BULL. 33, 1963, P. 30 Deposit:: MONT. BUREAU OF MINES & GEOL. MEM. 31, 1950, P. 92 Deposit:: CROWLEY, F. A., 1963 , MINES AND MINERAL DEPOSITS (EXCEPT FUELS) SANDERS COUNTY, MONTANA: MONTANA BUREAU OF MINES AND GEOLOGY, BULL. 34 , PP. 25 - 26 . Deposit:: GILBERT, F. C., 1935 , DIRECTORY OF MONTANA MINING PROPERTIES: MONTANA BUREAU OF MINES AND GEOLOGY MEM. 15 , P. 70 . Production:: CROWLEY, F. A., 1963 : MONTANA BUREAU OF MINES AND GEOLOGY BULL. 34 , PP. 25 - 26 .