G’day; if anyone thinks that they might use niello alloy as a “black
metal,” they’d better have another think. It is very hard - about
as ‘easy’ to grind into powder as a lump of glass. But it is
completely unworkable. A blow from a hammer shatters it. It melts
only a little above the melting point of lead solder. One might be
able to cast small items from niello; you’d have to experiment. It
is cast into little sticks by pouring the melt into a piece of angle
iron, and one applies it by heating the work and touching the places
where it can flow into engraving or interstices in a carved pattern,
and then it flows as easily as wax on a hot metal does. And has to
be filed and otherwise abraded off the parts where it is not wanted.
It is a lovely black and sticks immovably to sterling and is
extremely durable, vastly more so than ‘liver of sulphur’ or lime
sulphur, which produce a black which soon rubs off. You’ll have a
job buying it though. And as for making it - well, bin there; done
that, and it took three days to get rid of the resultant bad cough
and sore chest. – Cheers for now,
John Burgess; @John_Burgess2 of Mapua, Nelson NZ