barzilla

I turned the coin over to Ken Potter, who is a well-known coin error expert. Coincidentally, we share the same employer. I sent a scan over to Fred Weinberg in California and he ventured that the coin was machined, but 64x magnification shows no tool or grinding evidence. Ken will figure it out, no doubt, but he did say that he had never seen the like in his 45 year numismatic experience. He labelled it a "monostrike obverse" which is new terminology, at least to me. 64x shows tiny cuds of material on the bevelled edge portions. I'll post the results after I next see Ken. Thanks for all the input.

Hi, all. I'm over in the States and I was given a box of coins and such that belonged to my dad who served in the US Army during WWII. Amongst these coins was what I first took to be a button, but upon further examination determined to be a one-sided 1942 threepenny coin. By one-sided, I mean that the dated side is crisp and clear, but the opposite side, the one normally featuring the king's effigy, is completely smooth and blank. The edges of the coin begin to taper immediately and continue for about 5mm all the way around. The edges are slightly convex. The weight of the coin is approximately 3/5 of a normal 3d coin. I can only surmise that this was the bottom coin of two blanks struck simultaneously. There is absolutely no evidence of grinding or machining and the patina on the coin probably dates from the war. The reverse design is perfectly centered. Can anyone tell me of similar coins, or how else this coin might have been formed? Can anyone refer me to an authority on such coins. It simply must be some type of mint error, but I have never seen the like and I've been collecting since 1958. Thanks

Well, not to discount any possibilities, but the border isn't quite concentric as it would be if turned in a lathe or grinding machine. Besides, machine processes leave tell-tale evidence in microscopic scratch patterns or tool- marks. Furthermore, there are no edgemarks where it was mounted into jewelry. Besides, the easiest way to mount a hanger to brass is to simply solder it on. In my opinion, it was swaged (squished) into this form. I have seen most machine processes in my past 40-year career as a machinist and tool and diemaker. This item shows no evidence of any process which I am familiar with, beyond swaging. If two blanks were loaded, one atop the other, and the press closed under pressure, then either the collar would split or break, forming a broadstrike (not this case), or, if the material was soft enough, it could be swaged to the outside of the die until the die was completely closed, which would establish the edges by shearing and trim off the excess material to the outside. Of course, that would leave a corresponding "cupped" partial blank bearing the obverse. Considering that the thickness of this piece is .088" or 2.24mm and the normal 3d thickness is .103" or 2.59 mm, I could easily imagine the corresponding piece being so thin (.015") that it was either destroyed in the process or discarded by the mint when discovered as scrap, along with the excess material from the double blanks, which would have necessarily had to be cleaned out of the coining press in order to continue normal operation. My question, to you fellows, is whether any of you have seen or heard of such a thing. If this curio should turn out to have any value, my 90-year- old mother could certainly use a small cash infusion. I think that I mentioned that I've been collecting coins since 1958. I'm just mostly unfamiliar with British issues except for the ones contained in this small accumulation. Better yet, is there someone, there, in England, who could authenticate this piece? Someone who wouldn't charge more than a reasonable fee for doing so, I mean. I've seen hundreds of double-strikes but never one that wasn't misaligned somehow. This piece is a mystery to me. However, I will state unequivocally that is hasn't been turned in a lathe nor ground with any type of stone which would have been available in 1945 when my dad returned from military service and that is has sat, unmolested, in one dresser drawer or another in my mother's house ever since, along with several other GB coins from that exact era. I do not know where my dad was stationed, only that he was a military policeman in the US Army Air Corps during that time. If any of you know a collector of coin "errors" it might be helpful to contact him. Any and all input is much appreciated.

I measured the coin with calipers and the small diameter is approximately 17.78 mm. A 1944 farthing measures approximately 20.17 mm diameter. A 1944 sixpence measures approximately 19.35 mm diameter. The coin measures 2.24 mm in thickness. A 1943 3d measures 2.59 mm in thickness.

And this.

How's this?

I'm trying to get my scanner working so I can send a photo. I am a tool and die maker by trade and I can say, without reservation, that this thing has no toolmarks of any kind. I thought that perhaps the soft brass of a lower of two blanks might have been swaged out of the collar somehow and sheared off by the die itself. The coin isn't worn enough (barely, at all) on the legible side to make me think that the opposite side would be any worse for wear. As I mentioned, the tapered edges are convex and quite uniform. Additionally, the edges are paper-thin where they are full-size and bear no evidence of being chucked in a lathe, for example. The taper starts immediately from the lead edge. Give me a little time to reinstall the software on my scanner and I'll forward a couple of photo's. Meanwhile, say for the sake of discussion that this is legitimate. Has anyone ever heard of such a thing? Thanks