This group of certificate stubs and cards is grouped into four separate batches as follows: Miners' Certificate Cards and Stubs, which date from 1937 and 1938; Machine Runner and Cutting, Loading, and Drilling Machine Operators Certificate Stubs, dating from 1938 through the late 1950s, possibly the early 1960s; Miners' Certificate Stubs which date from the late 1930s; and Miners' Certificate Stubs dating from 1939 through roughly 1965. The bulk of the stubs and cards date from 1937 through 1955, and all provide excellent genealogical data on rank-and-file miners and other mine workers who labored in the bituminous fields of western Pennsylvania. Specific information found in each batch of material includes the following: Miner's Certificate Cards and Stubs, 1937, 1938 (81 boxes): name of miner, age of miner (not found on all cards), address of miner, certification number, application number, date of issue, employer, and mine number. Index cards constitute the bulk of this series, however, for some reason the run of index cards becomes a run of certificate stubs after Box 68, beginning with the stub for John Sagan. These stubs are stylistically different from the ones described below, but convey the same type of information; Machine Runner and Cutting, Loading, and Drilling Machine Operators Certificate Stubs, 1930s-1960s (12 boxes): stub number, name of miner, address of miner, place of birth, date of birth, mine where employed at the time of exam, company name, mine experience (some stubs provide a specific number of years of machine experience), place of examination, date of examination, date of certificate issuance, and bituminous inspection district number. Miner's Certificate Stubs, late 1930s (6 boxes): stub number, name of miner, address of miner, place of birth, date of birth, mine where employed at the time of exam, company name, mine experience, place of examination, date of examination, and date of certificate issuance; Miner's Certificate Stubs, 1939-1965 (25 boxes): stub number, name of miner, address of miner, place of birth, date of birth, mine where employed at the time of exam, company name, mine experience (in years), place of examination, date of examination, date of certificate issuance, and bituminous inspection district number. Also present are twenty-six microfilm rolls. All refer to the bituminous coal region of western Pennsylvania, with the first sixteen rolls apparently duplicating the Miners' Certificate Cards (1937, 1938) and the last ten containing original data, specifically: four rolls of Mine Foreman certification stubs and certificates, dating from roughly 1939-1966 (bulk 1940s), organized numerically by mining district then alphabetically by surname; four rolls of Mine Foreman certification stubs and certificates, dating from roughly 1966-1987 (bulk 1970s), organized numerically by mining district then alphabetically by surname; and two rolls of Shot Firer Certifications, 1938-1983, arranged alphabetically by surname. The cards and stubs on these rolls are NOT in precise alphabetical order; it is recommended to check throughout the run of a specific surname letter if an individual cannot be found in the normal alphabetical sequence.