Machine doubling yes machine treble-ing?

And another..

 

Log in or Sign up to hide this ad.

I think my own research proves its not so rare. However a good grade with clear tripled lettering seems a little more tricky to find.

 

1939 is the first year of the series.

The pictures shown are the sellers images.

 

Question is; does an example exist with clear trebled lettering as wide as the widest I have shown.

 

From 1901 through to 1938 for KM#29 20 R the metal used was nickel and the weight was 4.00 gram, 21mm.

In 1938 KM# 29a the alloy was changed.1938 to present day the alloy is noted as copper-nickel. With a weight of 4.20 gram. 21mm.

So in the transition of the alloy and the changing of the weight.

Is it possible this plays a roll in the variety I bring to your attention.

As complete novice I naturally dont have the understanding of the process or sequence of events that lead to doubled and tripled die coins.
Thanks.

 

Regular doubled dies are a problem in the die production due to misalignment during the annealing and transfer of the image from a master die.

Mechanical doubling damage occurs when the die holder is disfunctional and able to move or chatter , etc, producing a doubling effect when striking, rising, or ejecting the coin. Twice is more common, more is unusual. This multiple MDD strike on 1970 cent.
Jim

 

Thank you for your informative response.

Im assuming the master dies are a negative impression? I would imagine once engraved it is heat treated to harden the master. Then the master can impress the design into an annealed die which can then be used to strike coins is that correct?

A die crack can be related to the work hardening of the dies as they are used?
Thanks

 

I suppose if the dies are made from a tool steel maybe they are left soft enough to not work harden and split but hard and resistant enough to strike copper alloys all day without too much wear. Because its worth noting hard metals when work hardened crack easily..

 

I awnsered most of my questions reading up. Originially I thought the coin received 3 strikes. Now is it correct to say the die used was subjected to hubbing three times? In which was an attempt to prolong the life of the die by trying to restore detail as it wore out?

Am I correct in thinking a double die can only occur from the hubbing process?
For example an engraved die is not subjected to hubbing or at least not to obtain the initial design?

Or an engraved die can be heat treated to use as a master hub to then make the working dies.

Sorry if im over complicating things.

 

More than 2 hubbings were usually for higher definition coins such as proofs or also for extra large diameter coins, 2 was the normal for circulation coins before the modern single-squeeze die production method, and some feel a single squeeze can produce a doubled die, and some think it is not possible, but you will find they are supported by many.

Some are made by a working die being used for a master die or by itself to strike reproductions such as the Bashlow restrikes in many different compositions, but the defacing marks were still there.
https://www.ebay.com/itm/1861-1961-...-Nickel-Breen-8012-Uncirculated-/192604152356

most are much lesser prices depending on the composition. I forget which book said the nickel one was very scarce since the metal was too hard to mint and the die started breaking up.

several people have defaced dies that were sold as scrap for a while and made their way through the market. Jim