Working with ancient bronze

Jewelry Discussion
1

I am interested in working with ancient bronze. does any one know of
a source in London, preferably, or UK?

2

Hi Judy,

The only source I know of at all is Rio Grande (USA).
(www.riogrande.com) They’ve got copper/tin bronze as casting grain.
I used it for years at SBCC, with great results for casting. I did
some cast-then-forged projects with it with limited success. It’s a
lot more brittle than modern “bronzes”.

Sorry I couldn’t help with a UK supplier.

Regards,
Brian Meek.

3

Hi Judy,

I am interested in working with ancient bronze. does any one know
of a source in London, preferably, or UK?

I can only tell you from the colonies here in Australia, that
ancient bronze is something you have to make yourself, but it’s a lot
of fun.

What’s your set-up at the moment, I can make suggestions for budget
bronze alloying.

I have some friends in the UK that do historical re-enacting, and
they may make their own bronze. I could ask if you like.

Regards Charles A.

4

I bought some and needed more so I melted copper (mostly wire) then
added tin (had it for casting tin ((pewter)) pieces) and it was
great. So if no supplier, get copper wire and tin and make your
own…

John Dach

5

Hi Brian,

The best time to use 90/10 is when it’s first alloyed imo. Every
subsequent re-melt removes tin.

I’ve never had a problem with ancient bronze being brittle until I
re-melted it.

Regards Charles A.

6 
I am interested in working with ancient bronze. does any one know
of a source in London, preferably, or UK?

thank you to everyone who replied to my post. Charles, my setup is
very simple, just a crucible and torch. I’m going to get some tin, I
have copper, and give it a whirl. just going away for three weeks so
will have to wait till I get back… tks again

Judy

7

It’s my understanding that the newish bronze PMC is an ancient-
meaning copper/tin- alloy.

However, the bronze wires etc. that Rio Grande sells to go with it
are not necessarily copper/tin; I ordered some 18-ga (1mm) wire, and
while as I recall the catalog said it was copper/tin, I got a modern
phosphor bronze wire.

Amanda Fisher

8

I seem to recall that the metallurgy of the ancient bronzes was quite
variable, and could include all kinds of ‘contaminates’ as traces
from the original ores; and that occasionally lead was deliberately
added to improve ‘pour-ability’; not so great modern usages, though.
(Not a metallurgist, just an interested bystander) Betsy

This might help some;
http://web.comhem.se/vikingbronze/

9

Hi Betsy

This might help some; http://web.comhem.se/vikingbronze/

The webmaster of that site is a really nice guy, we had him out here
in Australia for a convention, demonstrating his dark age casting
theories.

When we say ancient bronze we are talking about an average bronze.

The contaminants can range from the addition of non-ferrous to
adding ferrous. Perhaps the caster ran out of tin and threw what he
had to hand into the mix, deliberate, or accident, at that period of
history records are slim pickings.

Bronze varied in recipe and in China there were Imperial edicts in
place to control the tin to copper ratio when making specific items.
However lead could be added liberally.

Interesting about the pour-ability, I was under the assumption that
lead was added to increase ductility… I’ll have to look into that.

Regards Charles A.

10 
thank you to everyone who replied to my post. Charles, my setup is
very simple, just a crucible and torch. I'm going to get some tin,
I have copper, and give it a whirl. just going away for three weeks
so will have to wait till I get back... tks again

The torch will determine your course of action.

If the torch has a lot of grunt, then you can alloy in an open
crucible. If the torch is small you need to concentrate that heat in
a furnace, but you can make a furnace body for micro melts for about
$20 Australian.

Regards Charles A.

11 
I seem to recall that the metallurgy of the ancient bronzes was
quite variable, and could include all kinds of 'contaminates' as
traces from the original ores; and that occasionally lead was
deliberately added to improve 'pour-ability'; not so great modern
usages, though.

That’s about the size of it. It’s one of the reasons that
archaeologists and museums are now far more likely to use the phrase
“copper alloy” than “bronze”, “brass”, “gunmetal” etc.

For example, the Museum of Fine Arts did an analysis of several
dozen of the copper alloy objects in their medieval collection in the
early 1990s, and found that not only are the copper, tin, lead and
zinc percentages all over the place, often they varied within
individual parts of objects composed of multiple parts. They
published it as part of catalog of the collection. (ISBN
0-87846-327-5).

Most of the recent archeology finds, like the work on the Thames,
and York have done similar analysis of the copper alloy objects.

Ron Charlotte – Gainesville, FL