16mm Bronze. The Byzantine tetarteron or “quarter coin” was introduced about 1100 AD by Emperor Alexius 1 as part of his coinage reform. It replaced the follis after the “cupped” trachy had been overused. The follis was debased and smaller. usually with the emperor on one side and Christ or a Christian symbol on the other side. Guaranteed authentic by Poor Richard’s Certified Classics; ancient, medieval, and Biblical coins.
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