I'm sure you have the pics like shown here.
http://www.antiquegamblingchips.com/mfgchip.htm
(that pic is from my company btw)

That is BEFORE they go into the press. Let me show you what happens when they are pressed. See below for a chip I just broke the edge off.
When pressed the body of the chip is squeezed outwards and it pushes the clay of the insert outwards until often only a sliver of clay remains. Sometimes it squeezes right through to the outside and you end up what are referred to as split spots. It happens more with some color combinations than others, due to the difference in melting temperatures in different color clay.
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