Blue lace agate rough stone from the original Ysterputz mine, Karasburg West Southern Namibia. This mine is no longer operational having closed some years ago. Blue lace from this deposit is now becoming increasingly difficult to find.
This distinctive stone is characterised by its blue colour and subtle white bands. It's a variety of the mineral chalcedony.
With the deposit in Namibia now being closed, most blue lace agate comes from Malawi and Zambia.