17th-19th centuries . I found a half dozen over the years , all in union dug in camps.
Bone buttons were often constructed in the home during the 17th and 18th centuries. Usually made of cow or pig bone, the raw material is soaked or steamed to soften. It is then separated into sheets (thickness of the desired button), and a circular saw is used to cut out and remove the button blanks. These are polished, and holes are drilled into the body to allow sewing onto garments. A few of the later ones from the 19th century are mounted on metal shanks. Plain bone buttons tend to be utilitarian in nature, such as fastening undergarments. Carved or inlaid bone buttons were produced in the second half of the 19th century in factories, and were intended for fancy outer wear. Not only buttons are recovered, but the strips of prepared bone with holes cut from them for blanks are recovered in site excavations.
