What are "assay coins"?

obversity

I was reading an article in CW from a few weeks ago about the California commem. where it states "...for a net mintage of 86,594 coins, including 200 assay coins.

What are "assay coins"?

Thanks for helping this newb.

relayer

An assay is when the metal content has been measured and certified - usually by a government official.

I'm not sure about the 200 coins refered to here, but I would assume an assay was done by the Department of Treasury.

100proof1957

seems to me the assay coins were minted before the SF mint was opened

as well as most coins minted before 1857 in California were private issues and maybe as late as 1869 or later

made to facilitate trade during the gold rush

DaveG

The reference is to withholding a certain percentage of each batch of coins minted - these coins were withheld from circulation and sent to Washington for the annual assay (a test of each Mint's product to ensure that it was producing coins of the correct alloy and weight).

Obviously, these assays ended when the Mints stopped producing coins of precious metal for circulation.

If you're interested in learning more about the annual assay, there are several books that discuss the process. As I recall, David Tripp's book about the 1933 double eagle (Illegal Tender) had a nice discussion about the assay.

GoldenEyeNumismatics

<< <i>The reference is to withholding a certain percentage of each batch of coins minted - these coins were withheld from circulation and sent to Washington for the annual assay (a test of each Mint's product to ensure that it was producing coins of the correct alloy and weight).

Obviously, these assays ended when the Mints stopped producing coins of precious metal for circulation.

If you're interested in learning more about the annual assay, there are several books that discuss the process. As I recall, David Tripp's book about the 1933 double eagle (Illegal Tender) had a nice discussion about the assay. >>

yep, he nailed it right on the money.

obversity

Aha! I see. Thank you all very much.

robertpr

So were the coins destroyed in the assaying process? Were they simply measured and weighed, or was melting or other destructive action part of the process?

DaveG

A certain percentage of the coins sent to be inspected by the Assay Commission were destroyed by being assayed - the process was destructive. It has been a while since I read about the process, but the coin was either melted or rolled flat and then a portion was melted.

I don't recall specifically what happened to the coins that weren't selected to be assayed, but I don't think they generally entered circulation. They may have been returned to the Mint to be melted.

PerryHall

Then there is also Assay Commission Medals which were issued to the commission members and are highly collectible.

RWB

After 1873 there were two kinds of “assay coins.”

“Special Assay” coins were samples selected from each delivery of gold and silver coin, typically two examples. These were sent to mint HQ in Washington where they were weighed, measured and the alloy assayed to verify that the coins were within legal tolerance. In effect, these were samples of ordinary production. All of these coins were destroyed as part of the assay tests with the various mints being credited for the bullion value.

“Annual Assay” coins were selected from each delivery at the rate of 1 for every 2,000 coins during the calendar year (this varied with changing mint regulations). These pieces were shipped to Washington (sometimes Philadelphia) in sealed boxes or packets and opened at the annual meeting of the Assay Commission in Philadelphia. Examples were selected by citizens on the Assay Commission and counted, weighed and assayed much like the special assay coins. After the commission had prepared its report, the members occasionally purchased pieces from the unused assay coins as souvenirs. Leftover coins were placed in circulation.