How proof coins are made. 1 1

[RWB]

I'm preparing a small article about how "proof" coins are made. It begins with the first US Mint products and ends about 1969 with the new Lincoln cent obverse. This is not about individual coins, but concerns "How" and not "Why."

If members have specific questions about proof coin manufacture, please drop me a note or post here. I will attempt to incorporate answers into the article.

[Henri Charriere]

On 12/6/2021 at 2:15 PM, RWB said:

I'm preparing a small article about how "proof" coins are made....

If members have specific questions about proof coin manufacture, please drop me a note or post here. I will attempt to incorporate answers into the article.

My understanding of proof coins is it is a process, not a grade, and not all are created equally, e.g., "matte" [finish] proofs.

If you were to address these two aspects, firmly and with finality, I would be more than satisfied.  (I am not even going to ask who or what motivated the powers that be to officially offer them in sets beginning in 1936, or thereabouts.)   🐓 

[RWB]

The answer to your 1936 proof coin question in in my book United States Proof Coins - 1936-1942. In many respects it is more detailed than the SG book.

[Henri Charriere]

On 12/6/2021 at 6:29 PM, RWB said:

The answer to your 1936 proof coin question in in my book United States Proof Coins - 1936-1942. In many respects it is more detailed than the SG book.

[Looks like I am going to have to dispense with the "wordsmithing" routine and become a functionally literate, well-educated human being.]   🐓 

[RWB]

Thanks all for the posted and private "proof coin manufacture" comments and questions. I've completed the article and it will be submitted for publication on Monday Dec 13.

[GoldFinger1969]

When did proofs first have the mirror-like surface ? 

Lots of Morgan and Saint proofs were better struck than business strikes but nowhere near super-reflective (esp. the gold Saints).

Edited December 13, 2021 by GoldFinger1969

[RWB]

On 12/13/2021 at 1:17 AM, GoldFinger1969 said:

When did proofs first have the mirror-like surface ? 

Lots of Morgan and Saint proofs were better struck than business strikes but nowhere near super-reflective (esp. the gold Saints).

From the earliest US Specimen/Master coins. This was in imitation of British proofs especially samples from Matthew Boulton and others.

[RWB]

The article was submitted to The Numismatist this morning. I have no information on publication date.

Update - at present publication is planned in two parts for January and February 2023...over a year from now.

Again, thanks to all!

Edited December 13, 2021 by RWB

[GoldFinger1969]

On 12/13/2021 at 11:13 AM, RWB said:

From the earliest US Specimen/Master coins. This was in imitation of British proofs especially samples from Matthew Boulton and others.

Around the 1930's, right ?  Might have been with the new Washington Quarter if I recall.

[RWB]

On 12/13/2021 at 8:02 PM, GoldFinger1969 said:

Around the 1930's, right ?  Might have been with the new Washington Quarter if I recall.

The first generally accepted US master coins (proofs) date from 1818. Normal practice was to polish the fields and let the relief hold its acid etch (frost) as long as it could. Occasional touch-up might have been attempted because neither surface lasted very long. But -- there was little reason to make more than a couple until the 1830s and rise of collectors. By the 1850 it became common to polish planchets also and this helped avoid frequent repolishing of dies.

Edited December 14, 2021 by RWB

[GoldFinger1969]

On 12/13/2021 at 9:11 PM, RWB said:

The first generally accepted US master coins (proofs) date from 1818. Normal practice was to polish the fields and let the relief hold its acid etch (frost) as long as it could. Occasional touch-up might have been attempted because neither surface lasted very long. But -- there was little reason to make more than a couple until the 1830s and rise of collectors. By the 1850 it became common to polish planchets also and this helped avoid frequent repolishing of dies.

But when did the mirror finish become common place ?  I know with Saints the proofs weren't that impressive and they could never decide between matte and satin finishes.

Edited December 14, 2021 by GoldFinger1969

[RWB]

On 12/14/2021 at 12:20 AM, GoldFinger1969 said:

But when did the mirror finish become common place ?

From the earliest usage in British and French mints, and by Boulton's Soho Mint and others. The first generally accepted US examples are dated 1818.

SG proofs were either satin or sandblast - but collectors really did not like either and wanted mirror-polished fields.

[olympicsos]

On 12/14/2021 at 12:20 AM, GoldFinger1969 said:

But when did the mirror finish become common place ?  I know with Saints the proofs weren't that impressive and they could never decide between matte and satin finishes.

Actually Saint Gaudens objected to a mirror finish IINM. The matte proofs look very nice when undipped and not messed with. I love them.

[RWB]

Very few sandblast proofs survive in undipped condition.

[GoldFinger1969]

On 12/15/2021 at 12:47 PM, olympicsos said:

Actually Saint Gaudens objected to a mirror finish IINM. The matte proofs look very nice when undipped and not messed with. I love them.

Were mirror-finishes creatable at that time ?  I don't recall seeing too many gold coins with that finish.  Silver Morgans were easier to mirror-finish.

Maybe I'm guilty of comparing them to today's mirror-finishes with light-years better technology.

 

Edited December 15, 2021 by GoldFinger1969

[VKurtB]

How about touching on the Large Date and Small Date as it pertains to the 1970-S proofs?

[Conder101]

On 12/15/2021 at 1:22 PM, GoldFinger1969 said:

Were mirror-finishes creatable at that time ? 

Yes, the Liberty head proofs for 1907 (and earlier) had mirror fields.  Mintages tended to be low so they tend to be cameo as well, so only the fields are mirrors.

[RWB]

On 12/15/2021 at 1:22 PM, GoldFinger1969 said:

Were mirror-finishes creatable at that time ?  I don't recall seeing too many gold coins with that finish.  Silver Morgans were easier to mirror-finish.

Maybe I'm guilty of comparing them to today's mirror-finishes with light-years better technology.

 

All US master and proof coins (the same things) had mirror-like polished fields. SG and Pratt gold were the first ones to have a medal finish rather than a normal coin proof finish.