A graded coin is one that has been sent to a professional grading service and put into a "slab" (a clear coin protector case). It will have the coin type as well as the grade of the coin. They are graded from G2-70. 70 being the highest and best the coin could ever be. The grade is determined by eye appeal, physical condition-(scratches, finger prints, toning, other factors), errors -many other factors. Your coin may be in a plastic case but does not sound like it is graded. If you up load a picture, there are people here who will help you determine an approximate value and series of the coin.
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