Join Date: May 2014
thanks for the info!
I figured out that under the newer blackening there is (active) rust partially. So I removed this new blackening. Now one can see different layer of older colours. The lowest layer seems to be a homogenious greyish/black, partially a bit blueish, thin cover. It looks like burnished. Was burnishing already known and used around 1600? Or might that have been made in later times?