Hexagram was a large silver coin of the Byzantine Empire issued primarily during 7th century AD during the reigns of Heraclius, Constans II, and Constantine IV. It weighed about 6 grams.

2018-04-25 - Live Coin Catalog's improvements / description improving

5 coin descriptions were improved from 2018-04-18 to 2018-04-25
One of them is:

    1 Denarius Roman Republic (509BC-27BC) S ...
group has   

2018-06-29 - Historical Coin Prices
1 Thaler Kingdom of Bavaria (1806 - 1918) Silver M ...
Coin prices from public sources