Gigantic coins, written and illustrated by Oesho

[Oesho]

Dear Peter, The gigantic coins were not cast! They were definitely struck. If you enlarge, for instance, the pictures of the 1000 Tola piece of which I sent you the images, you may observe some effects of double striking. We can all guess the way they may have done it, but technically it was done by some kind of hammering. Even when the planchet was heated, it no doubt, required a tremendous amount of energy to impress an object of 21 cm in diameter. This can, for instance, be done the way they drive piles nowadays. The Mughals had all kind of military equipment. So it would not be that difficult to imagine that they may have had such a kind of ‘pile driving’ equipment with a heavy (steel)block, in between two guide poles, falling from some height on the dies. It would be novelty in minting, but not impossible. The resonance, caused by such a falling block, may account for the double striking effect, which you may observe on the obverse and reverse of the coin. I have no written evidence found anywhere how they actually did it, but it may just be a possibility.

[Salvete]

How do you strike a nearly 12 kg coin and get a clear, reasonably uniform impression? Multiple strikes, elephant 

  I remember a lecture by a member of the ONS, probably at the Fitzwilliam Musem in Cambridge UK, over 15 years ago, when it was explained how the strike was made.  As best as I can remember, this is what was said.

  Apparently there is no way to do it in one go.  Separate dies were prepared for each bit of the coin and the  part-dies were carefully placed and struck separately.  That is why most of the coins are the 'square area' type and similar, where clear divisions could be made between one part-die and its neighbours without the join being too obvious.  We were told that on most surviving specimens a careful examination reveals the 'joins'.  The whole process of preparing flans and multiple strikes was time-consuming, but time is money, and the Great Mughals were never short of money!

  These 'coins' are art, without a doubt, and like so much great art, the surviving specimens are reportedly mostly owned by giant corporations and locked away in bank vaults.  In the treasury is where they would have spent most of their lives in Mughal times, of course, so nothing much has changed over the last 450 years.  Not what I'd do with them, but of course I shall never have any say in the matter!!!

  My memory is not perfect, so I hope I am not misleading anyone about any of it.

  Salvete

[Oesho]

Apparently there is no way to do it in one go.  Separate dies were prepared for each bit of the coin and the  part-dies were carefully placed and struck separately.  That is why most of the coins are the 'square area' type and similar, where clear divisions could be made between one part-die and its neighbours without the join being too obvious.  We were told that on most surviving specimens a careful examination reveals the 'joins'.  The whole process of preparing flans and multiple strikes was time-consuming, but time is money, and the Great Mughals were never short of money!

Dear Salvete,
From the high resolution scans of the 1000 Tola of Jahangir, with circular legends, it is very obvious that they used one single die. A die put together by various parts would be impossible it would break into pieces immediately when hit by an hammer. Neither can it be done by patch wise stamping (central part and margins) as the design with a flowering background (so often seen on coins of Jahangir) continues all over the surface. It is an outstanding piece of calligraphical art. It must have been produced with a single die and with a large blow of kinetic energy to create even the impression of the most minute fine details. The images I have are of about 17 Mb for each obverse and reverse and are a bit to heavy to be sent by e-mail, otherwise you may come to the same conclusion. The observations of the speaker, you referred too, cannot not be true.

[Salvete]

Thank you, Oesho.  As I said, I have no personal knowledge of these coins, and have never seen any of them.  I simply repeated what was said many years ago during a discussion of techniques used at Mughal and later Indian mints, most of which seemed to make sense then, and continues to seem reasonable now, in case it might be helpful.  Clearly it was not, so sorry to anybody who read it.  There was another error made during the talks, concerning the details of preparing steel dies, so perhaps I should have been a little less trusting in other data offered then.  Onwards and upwards.

Salvete

[capnbirdseye]

Looking on the other thread linked to here ( most rare coin) regarding how such coins were struck then I think the general rule with hammered coins applies in that they are raised to red heat otherwise the flan will crack, rapid cooling down applies as soon as it touches the cold lower /fixed die. Using a collar will keep the coin centred but is usually unheard of with hand made Indian coins except for Nazarana coins as it slows down the process considerably as the coin expands & then has to be knocked out.

I saw a demonstration of coin making using original dies for Elizabethan shillings many years ago & it prompted me to have a go myself.
I crudely engraved both dies with my name in a circle in English one side & Nagari on the other.
 I tested it on lead first & was well pleased & set about heating up some badly worn UK silver shillings in my forge.  D unless the metal was almost cherry red it required more than one strike & cracked the flan every time  & if the first strike didn't go deep enough then the die would move a fraction & double the image. All in all it would take incredible skill to strike a huge coin such as the 1000 mohur  but I dare say they took multiple attempts & remeltings to get it just right.  In modern machinery strikes I presume the blanks are annealed  first so they can be struck cold ?

[Overlord]

I can no longer see the pics in Oesho's invaluable article, just red crosses. Anyone else facing this problem?

[Bimat]

Anyone else facing this problem?

No, I can see all the scans very well!

Aditya

[Overlord]

Strange, now I see them too!

[Bimat]

Sometimes that happens with me too! Seems that Indian servers have some problem with these image hosting websites..

Aditya

[firdausei]

A very interesting thread... made good reading... One thing about the Mughals ... they left their mark everywhere ... whether coins or the warring fields, nevertheless this was a very interesting topic ... thank you all for your contributions.

[Oesho]

Dear Peter, The gigantic coins were not cast! They were definitely struck. If you enlarge, for instance, the pictures of the 1000 Tola piece of which I sent you the images, you may observe some effects of double striking. We can all guess the way they may have done it, but technically it was done by some kind of hammering. Even when the planchet was heated, it no doubt, required a tremendous amount of energy to impress an object of 21 cm in diameter. This can, for instance, be done the way they drive piles nowadays. The Mughals had all kind of military equipment. So it would not be that difficult to imagine that they may have had such a kind of ‘pile driving’ equipment with a heavy (steel)block, in between two guide poles, falling from some height on the dies. It would be novelty in minting, but not impossible. The resonance, caused by such a falling block, may account for the double striking effect, which you may observe on the obverse and reverse of the coin. I have no written evidence found anywhere how they actually did it, but it may just be a possibility.

Due to the reply of ‘firdausei’ to this thread, I read my remark about the possible minting technique used to produce these giant coins. This summer I was at a meeting at Kultur- und Stadthistorisches Museum in Duisburg. In this museum the preserve a really extraordinary minting machine, a falling hammer device. In my remark  above, I suggested that such a device “would be novelty in minting, but not impossible” and see here it is. The machine is still in working condition and a souvenir made on this minting device is shown below as well. A similar device, probably of some more robust size, must have been used to produce these giant Mughal coins.

[Figleaf]

Extraordinary. It looks like the same principle as the guillotine. Not a trace of double strike on that medal (but it needs wiping off what looks like fingerprints.) I know of a similar device for cutting planchets but had never seen anything like this.

Peter

[Coinsforever]

Due to the reply of ‘firdausei’ to this thread, I read my remark about the possible minting technique used to produce these giant coins. This summer I was at a meeting at Kultur- und Stadthistorisches Museum in Duisburg. In this museum the preserve a really extraordinary minting machine, a falling hammer device. In my remark  above, I suggested that such a device “would be novelty in minting, but not impossible” and see here it is. The machine is still in working condition and a souvenir made on this minting device is shown below as well. A similar device, probably of some more robust size, must have been used to produce these giant Mughal coins.

I guess such minting machine has been operating manually  only , instead of any electrical or mechanical force.

Products are just awesome. BTW may I request you what  could be  age of this machine  kept in museum .

Cheers

[Oesho]

BTW may I request you what  could be  age of this machine  kept in museum.

The fall hammer minting seems to have been in vogue already in the
16th and
17th century, particularly in
Germany
The equipment in
Duisburg dates from the end of the 19th century.

[Coinsforever]

The fall hammer minting seems to have been in vogue already in the
16th and
17th century, particularly in
Germany
The equipment in
Duisburg dates from the end of the 19th century.

Thanks for links. 

These minting machines are quite simple to use but it's incredible that  it produce quality coins.

Cheers