18:51 Farthing real variety or start of a simple cracked die.

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If you look at the bottom image you can see the faint line of the die crack. The coin was listed/sold as having a colon.

I'm aware a variety is listed for the 1851 Farthing with a purported colon.

Looks like the beginnings of a die crack rather than a colon to me.

 

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[Coinery]

I agree, almost certainly connected with the die crack!

[Paddy]

Could be they drilled a small hole in the die to limit the crack. It is a well known technique to drill a small hole at the end of a crack as it reduces the stress at the tip and so makes it less likely the crack will propagate further.

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1 hour ago, Coinery said:

I agree, almost certainly connected with the die crack!

Both coins are missing the serifs on the B of BRITANNIAR.

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56 minutes ago, Paddy said:

Could be they drilled a small hole in the die to limit the crack. It is a well known technique to drill a small hole at the end of a crack as it reduces the stress at the tip and so makes it less likely the crack will propagate further.

Interesting, do you think the images show that progression? A crack formed, two holes drilled and then the die deteriorated further to show the pronounced crack we see in the first image.

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I just noticed the following; 

https://aboutfarthings.co.uk/catalogue/farthing-varieties/

"Obverse 2e Die Fault resembles colon between 8 & 5 in Datal Figures (Image shows early stage of flaw, advanced stage can be seen in the enlarged image"

I saw a coin listed as having a colon and when looking at other 1851 farthings I noticed the example with the crack, aboutfarthings.co.uk has it spot on.

Edited 14 hours ago by absence of uniformity

[Paddy]

10 hours ago, absence of uniformity said:

Interesting, do you think the images show that progression? A crack formed, two holes drilled and then the die deteriorated further to show the pronounced crack we see in the first image.

I cannot say definitely that is the case, but it certainly seems a possibility. I suppose the other way would be if parts of the die were fragile and broke off around the nascent crack, but I don't think the metal used in the dies was usually that brittle.

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2 hours ago, Paddy said:

I cannot say definitely that is the case, but it certainly seems a possibility. I suppose the other way would be if parts of the die were fragile and broke off around the nascent crack, but I don't think the metal used in the dies was usually that brittle.

I engraved some coin dies in 1/12 scale for Dolls house money. I used mild steel and after striking 20 coins the mild steel dies deformed. I dont know but would imagine real coin dies are tempered to a certain degree making them less likely to deform like the dies I made. I tried striking gold, silver, bronze and copper all soft metals compared to mild steel, the fact my dies were not tempered they deformed. I quickly understood a highly polished die and more force when striking the dies produced much higher quality strikes. When I try it again I will anneal 01 tool steel engrave my obverse and reverse then temper them in order to harden the metal so I can strike more than 20 coins. There will be a trade off between a soft of a die that deforms with subsequent strikes and tempering the metal too hard the dies crack rather than deform.

If a metal cracks rather than deforms it suggests it is tempered or work hardened and with each subsequent strike the metal is probably hardening itself also. At a guess I would think a pair dies slowly harden over the working life of a pair of dies which may lead to crack dies??

I made a steel tube/collar inserted the bottom die into the collar then placed my metal blank into the collar then presented the other die and struck it with a hammer. Initially I was getting weak strikes, then started hitting it harder which produced much nicer strikes but ultimately deformed the dies.

Edited 2 hours ago by absence of uniformity

[jelida]

18 minutes ago, absence of uniformity said:

I engraved some coin dies in 1/12 scale for Dolls house money. I used mild steel and after striking 20 coins the mild steel dies deformed. I dont know but would imagine real coin dies are tempered to a certain degree making them less likely to deform like the dies I made. I tried striking gold, silver, bronze and copper all soft metals compared to mild steel, the fact my dies were not tempered they deformed. I quickly understood a highly polished die and more force when striking the dies produced much higher quality strikes. When I try it again I will anneal 01 tool steel engrave my obverse and reverse then temper them in order to harden the metal so I can strike more than 20 coins. There will be a trade off between a soft of a die that deforms with subsequent strikes and tempering the metal too hard the dies crack rather than deform.

If a metal cracks rather than deforms it suggests it is tempered or work hardened and with each subsequent strike the metal is probably hardening itself also. At a guess I would think a pair dies slowly harden over the working life of a pair of dies which may lead to crack dies??

I made a steel tube/collar inserted the bottom die into the collar then placed my metal blank into the collar then presented the other die and struck it with a hammer. Initially I was getting weak strikes, then started hitting it harder which produced much nicer strikes but ultimately deformed the dies.

What great fun! That is really rather clever, nice job!

Jerry

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19 minutes ago, jelida said:

What great fun! That is really rather clever, nice job!

Jerry

Thanks ! I started out with intentions to try and engrave reverse and obverse design of a penny, I quickly gave up on that. Impossible. I have a pantograph that I can mill metal but struggled with that because the dies are 4mm diameter even with a 6:1 reduction. In the end I engraved the designs freehand using a loupe, it was tricky. For a normal size coin I could print a guide/stencil on the 3d printer and using the pantograph mill the design into a steel die then temper it.

The more simple designs of hammered coins I could make something that resembles the real thing. Although I have no intentions of forging any coins.

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Here is the pair of dies and the coin I struck with them. This was the largest I made and because I spent a while engraving them I was more gentle with the hammer. The image shows the dies and the coin made using them.

Edited 1 hour ago by absence of uniformity

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Here you can see the mild steel die deformed after striking around 20 coins. To me its clear you need tool steel and the die must be tempered to some degree. But not so much its too brittle. But in its current state not suitable for striking coins.

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Here is all the dies I made with the different collars.

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I dont own a dollshouse myself but in my spare time I make objects for collectors (I'm amateur jeweller), here is 1/12 scale fully functional padlock.

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Here is a pair of 1/12 queen Anne flintlock pistols I made. https://www.youtube.com/shorts/JRH-9o-P6sg

Edited 42 minutes ago by absence of uniformity

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Fully functional teapots hollow spouts and removable lids.