Schmitt & Schmittdiel
This Detroit factory was run by the improbable combination of Henry Schmitt and Andrew Henry Schmittdiel. Their stamps were issued from August of 1872 to, in the case of the one-cent stamp, February 14, 1881. 14,714,276 were issued on silk paper and 17,766,320 on pink and watermarked papers. The copy above is on silk paper.
The Schmitt and Schmittdiel three-cent stamp was issued only until some time in 1878. 1,860,689 were printed on silk paper. The company was sold to Diamond Match around 1881.