Pyrite Sun. 8cm x 6cm, from The Gateway Mine, Sparta, Illinois, USA.
This Pyrite sun is a stunning example of this unique form of pyrite which also has an incredible metallic lustre. This one measures 8cm x 6cm with the typical colouring that occur in these fascinating formations. They are natural mineral disk of pyrite (iron Sulphide) with superb radiating ‘fan like’ patterns. The Pyrite sun is also known as the ‘Miners Dollar’. They got this name because coal miners would put them in their lunch boxes for protection. These were then sold to collectors are a way of topping up their wages. This particular specimen is from the Gateway Mine.
Pyrite suns are becoming harder to obtain because they come from only 7 locations worldwide. They occur between 60 and 75 metres underground in coal mines around Sparta, Illinois, USA. Of the seven mines that produce pyrite suns only one is now open and in production. They are completely natural and are over 300 million years old. Although ‘discs’ of pyrite can also occur in other locations, these ones from Illinois are unique because of their size. These fascinating pyrite formations are around 300 million years old. At that time a shallow marine lagoon was covering this part of Illinois. The actual suns occur in a thin bed of organic rich Anna Shale. One of the important factors being, that there was virtually no circulation within this lagoon. And additionally it was ‘anoxic’, without air.