Bronze Mortar Model Marked "1530"

cannonmn · 21st January 2012, 10:05 PM

Michael, thanks. I interpret your reply to mean that you think this piece was actually made in 1530, so if you have any doubt, please let me know.

I liked the casting and turning on it, and like you, the "1530" looked "period." However what bothered me was the rather thin and not-very-dark patina on the bronze. The piece does not look like it has been polished or at least not polished much, because the fine lines from turning and scribe marks on the muzzle are still sharply-defined.

Therefore, I was a bit surprised that there is still any bronze on the piece that is somewhat shiny or with little patina.

1. Have you seen other examples of 16th C. bronze with such a thin/light patina?

2. I predict my friend will want to know if you considered the possibility that this could have been cast somewhere other than in Germany or Austria. For example Baude and Owen were casting very fine pieces in England at about that time.

Matchlock · 22nd January 2012, 03:00 PM

Hi John,

There is always a certain possibility that pieces that look 'as new' are newly made and that that of your friend has been cast after a 1530 original. In order to tell one from the other a close examination would be necessary, including filing a small portion off the metal and having it spectro-analyzed in a laboratory. Original early-16th c. bronze or brass pieces contained a relatively high percentage of copper and silver, so even if overcleaned they mostly look a bit reddish.

As to the terminology of brass or bronze barrels, museum, auction houses and collectors alike tend to just label them 'bronze' as it sounds higher-value. We should, as always, go back the roots and confer the old terms. In 500 year old books and armory inventories, e.g. the Maximilianische Zeugbücher illustrated by Jörg Kölderer of Innsbruck/The Tyrol, where the Maximilian main armory was located, we never find the term bronze, just Messing (brass) or Kupfer (copper). Of course the difference between the two alloys is mostly a higher amount of copper in bronze.

Yes, I did see a few totally overcleaned pieces with even the tiniest spot of patina removed, and of course they looked 'as new'. What really bothers me about our mortar in discussion is the striking crispness of the concentric circles on the bottom and of the trunnions.

If this is a modern copy, of course it could have been cast anywhere; maybe it is even a museum replica.

Best,
Michael

cannonmn · 22nd January 2012, 11:23 PM

Quote:

What really bothers me about our mortar in discussion is the striking crispness of the concentric circles on the bottom and of the trunnions.

Thanks Michael. Well we know who ever made this used a metal-cutting lathe to make the two concentric rings on the muzzle and the very fine lines around the mid-section. They must have a very sharp, hardened steel cutter in use on that lathe, so the concentric circles on the base came from the same cutter. The divot in the center of the bottom is of course where the lathe center was positioned, and had to be drilled there before the lathe-turning could begin.

I don't know when precise metal-cutting lathes were first used, do you? What I know for sure is that this piece was completed with a very precise metal-cutting lathe.

21st January 2012, 10:05 PM	#1
cannonmn Member Join Date: Jun 2006 Posts: 161	Michael, thanks. I interpret your reply to mean that you think this piece was actually made in 1530, so if you have any doubt, please let me know. I liked the casting and turning on it, and like you, the "1530" looked "period." However what bothered me was the rather thin and not-very-dark patina on the bronze. The piece does not look like it has been polished or at least not polished much, because the fine lines from turning and scribe marks on the muzzle are still sharply-defined. Therefore, I was a bit surprised that there is still any bronze on the piece that is somewhat shiny or with little patina. 1. Have you seen other examples of 16th C. bronze with such a thin/light patina? 2. I predict my friend will want to know if you considered the possibility that this could have been cast somewhere other than in Germany or Austria. For example Baude and Owen were casting very fine pieces in England at about that time. Last edited by cannonmn; 21st January 2012 at 11:47 PM.

22nd January 2012, 03:00 PM	#2
Matchlock (deceased) Join Date: Sep 2008 Location: Bavaria, Germany - the center of 15th and 16th century gunmaking Posts: 4,310	Hi John, There is always a certain possibility that pieces that look 'as new' are newly made and that that of your friend has been cast after a 1530 original. In order to tell one from the other a close examination would be necessary, including filing a small portion off the metal and having it spectro-analyzed in a laboratory. Original early-16th c. bronze or brass pieces contained a relatively high percentage of copper and silver, so even if overcleaned they mostly look a bit reddish. As to the terminology of brass or bronze barrels, museum, auction houses and collectors alike tend to just label them 'bronze' as it sounds higher-value. We should, as always, go back the roots and confer the old terms. In 500 year old books and armory inventories, e.g. the Maximilianische Zeugbücher illustrated by Jörg Kölderer of Innsbruck/The Tyrol, where the Maximilian main armory was located, we never find the term bronze, just Messing (brass) or Kupfer (copper). Of course the difference between the two alloys is mostly a higher amount of copper in bronze. Yes, I did see a few totally overcleaned pieces with even the tiniest spot of patina removed, and of course they looked 'as new'. What really bothers me about our mortar in discussion is the striking crispness of the concentric circles on the bottom and of the trunnions. If this is a modern copy, of course it could have been cast anywhere; maybe it is even a museum replica. Best, Michael Last edited by Matchlock; 22nd January 2012 at 05:45 PM.