In coin collecting, coin grading is the process of determining the grade or condition of a coin, the key factor in its value as a collector's item.
Coin grading has evolved over the years to a system of finer and finer grade distinctions, particularly when talking about US coins. In the beginning, people collected ancients and there were two grades, new and used.
This evolved for a time to the letter grading system beginning with the lowest grade – Basal State (also Poor (PO)), then continuing Fair (Fr), About or Almost Good (AG), Good (G), Very Good (VG), Fine (F), Very Fine (VF), Extra Fine (EF or XF), Almost or About Uncirculated (AU), Uncirculated (Unc) and up to Brilliant or Beautiful Uncirculated (BU). Gem Uncirculated was roughly equivalent in usage to BU at that time.
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