User blog comment:Gsimenas/Call Gsi Button/@comment-37.128.219.93-20141114135802/@comment-6697950-20141114141215

I've already looked this issue up. I don't know about the first mention of gold coins, since that instance is referencing the web version of Progressive volume 2, while the story hasn't been translated into English.

However, for the second instance, I have looked up the raw of the part that was being referenced:

一瞬、自分のお腹で十万コル金貨がじゃらじゃら音を立てている想像をしそうになったが、すぐに振り払う

The 十万コル金貨 part is literally saying "100,000 col gold coins". So, the same metal is most likely used for more than one denomination.