Initially poker was played on riverboats and in bars and saloons in America on the west coast and Nevada. Poker was played with gold, gold dust and coins. Chips came later and were made from bone, ivory, paper, wood and a mixture of clay and shellac. The disadvantage was anyone could mix their own chips into the game. To overcome this problem the manufacturers began adding different designs in the chips for identification. The design could be engraved, embossed, inlaid or a paste-on sticker. Ivory chips were hand scrimshawed with numerals, initials, flowers, animals and many other designs. The ivory chips were custom made. Clay composition poker chips were made by many companies between the 1880′s and the late 1930′s. There were thousands of designs to choose from. Though most of the chips were a standard white, red, blue and yellow they could be made of any color. In the 1940s plastic became very popular. The chips were moulded and lasted for a long time and could come in any design. They were available in abundance. However the quality could not be compared with the chips made from natural materials. In the beginning casinos used silver coins for the slot machines. With the rise of silver prices in 1964 the casinos needed to substitute the silver coins. The Nevada Gaming Control Board after consulting the US Treasury allowed the casinos to use their own tokens to operate the slot machines. Most of the casinos in several jurisdictions are not allowed to use currency in slot machines. Tokens have been around for a very long time now but slowly the casinos are replacing the token machines with coin-less machines. These machines accept banknotes and print receipts for payout. These receipts can be used in the machines as well. Some casinos in Las Vegas have chips with RFID tags embedded in them. This helps the casinos to keep track if the chips and also establish the extent of the gamblers’ bet. It is also a safety precaution as it becomes difficult for anyone to reproduce the same. But this system is very expensive and eats up some of the profits. Today coins are made from clay composition, plastic, ceramic and the big rectangular ones called plaque are made from mother-of-pearl.