Guild Wars 2

Hi all, I’ve been out of the game for a while and hold some copper doubloons. Would anyone be able to explain the reason for their increase to ~6s? I notice they had a much bigger increase to 12-15s in late august but alas I was out of the country. I assume that they or a derivative played some role in a new item?

Thanks.

They are used to make Sunstone Nuggets which was used to make Sunstone Lumps which were then used to make Grow Lamps that cost a lot of gold.

Great, thank you very much!