134 



MARINE PRODUCTS OF COMMERCE 



As a first step a disk is cut out of a somewhat larger diameter than that required 

 for the button, then reduced to the size of the button by means of a triangular 

 steel file of fine temper and with a very obtuse point. Due to the considerable and 

 variable hardness of the mother-of-pearl only an expert workman can perform 

 the task satisfactorily; he must always be on the alert to feel the degree of re- 



FiG. 8-4. Facing and drilling pearl 

 buttons with Barry machine. 



(Courtesy American Pearl Button Co.) 



sistance and regulate the pressure of the tool. An expert operator can make from 

 12 to 22 gross of buttons in a day. The perforation is generally done by women, 

 one of whom can pierce in a day 30 gross of buttons having 4 perforations. After 

 these operations of forming and piercing, comes the work of polishing, also 

 usually performed by women. The buttons are firmly mounted and polished 

 by a strip of cloth impregnated with highly diluted sulfuric acid and by another 

 covered with tripoli powder. These are passed rapidly over the surface of a 

 turning lathe. 



American Methods. The shells are first sorted by hand according to species and 

 quality, then graded as to size by a machine called a classifier. The classified 

 shells are placed into large metal tanks or vats, or sometimes into barrels, in 

 which they are allowed to soak for a week or more, thus becoming soft enough 

 for cutting. 



The blanks are cut by means of a lathe fitted with a tubular saw, wooden plug, 

 and ratchet handle or lever; the latter gradually forces the rough shell against 

 the rapidly rotating saw. The waste shell is crushed and used for such things 

 as stucco, fish bowls, and grit for chickens. The blanks are classified by a machine 

 consisting of variously spaced rollers and are thus separated into different lots 

 according to thickness. They are placed in heavy slowly revolving tumblers and 



