Among my collection are chips (or plaques) from foreign countries, including mother-of-pearl (nacre) (MOP), bone and other material. Some of the MOP chips have attractive designs. Some in my collection are from unknown casinos but most are probably for home games. The bone chips from England are from sets clearly used for home play. The following are examples of my mother-of-pearl collection.
MOP Samples: Rich Hanover has an ivory chip with the same initial design and attributes it from the Casino  de Arecibo, Arecibo , Puerto Rico. http://www.oldpokerchips.com/NonNevada/Arecibo.htm  Note the number "77." Numbered MOP chips and plaques indicate they are casino chips.
See Robert Eisenstadt's home page where this chip is shown: http://www.antiqueggamblingchips.com/mother_of_pearl.htm The reverse is blank.
Another interesting design: Maya, Inca? Unknown chip.   The anchor design is seen in a number of casinos but this chip is unknown:   Another anchor chip. Note the number 1800.   One more sample:

CHIINESE LOO CHIPS. The Chinese game of Loo became popular in England and its colonies in the 17th, 18th & 19th Century. Most of the chips, although created by Chinese artisans were made for use in Great Britian and the Empire. Here are some samples.
                                                       
The serrated edge chips also collected by English ladies who use them around which to wrap their threads. I had to "fight" to keep one of the chips i located in a London market when a small but tough little woman tried to take it from me, saying she needed it for her threads. Rules of the game can be found at  http://www.pagat.com/rams/loo.html

Bone was also use for chips (among other things such as celluloid, paper and  rubber):

                                               

Antique & Gaming Poker Chips

MOTHER OF PEARL SAMPLES

Trav's Trail