Blue goldstone tumbled stones 20-30mm

Blaufluss: This is Gold River in dark.
With the typical sparkle / sparkle.
Real, he appears even more glittering than in the photo. ;-)
Blaufluss is like Goldfluss a synthetically produced stone!
The manufacturing process for Blaufluss tumbled stones is roughly similar to that of glass.
The stones are then ground like natural stones on the grinder.
These beautiful bulbous well-proportioned tumbled stones are called tumbled stones, but are hand-cut and polished by hand. Only then can you get the dark blue blue-flow stones so evenly.
A book tells that the Gold River / Blue River Stone was created when Italian monks tried to make gold. (... almost certainly this is a rumor.)