Funny you should ask <img src=icon_smile_big.gif border=0 align=middle> I've been doing some research in regards to the "crystal" that is used in turkey calls. I have found that the "crystal" is a man made type of glass and plexy glass. Actually it's even used to make trophys and reward plaques. Have also found that it's used for large windows and skylights since it holds off heat & cold better then glass or plexy. I've contacted one distrubter so far about pricing, but my problem is he doesn't sale it in the thickness I need. Wish I had some techincal information for ya' but this is all I have found so far. I like to use purple heart, rosewood, Wood Wise mystic stick and the hickory stinger on the "crystal" calls I own. The glass that I have bought to use in my calls so far has been straight up glass. I use double strength which gives more pitch then single strength glass and is also stronger. Have no idea what the major call companies use, but in the two glass calls I have made so far it sounds great. I like walnut, hickory, mystic stick and purple heart on glass. Dang sorry I just rambled.
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