Sintered Sac crossover..
Gemineye
Posts: 5,374 ✭
Would PCGS cross this Sintered Sac ???
......Larry........
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I believe
Menomonee Falls Wisconsin USA
http://www.pcgs.com/SetRegistr...dset.aspx?s=68269&ac=1">Musky 1861 Mint Set
PLEASE tell me "sintered" means "darkened" or "artificially toned" or smoething like that, and not "I-Am-A-Complete-Idiot-Who-Can't-Even-Spell-C-E-N-T-E-R-E-D".
<< <i> sintered- powdered metals pressed together in a mold under extreme pressures and heat
I believe >>
Gee, I sure hope so. It's hard to imagine even a Third World TPG being stoopid enough to spell "centered" that way.
Coins are not made by "sintering."
These planchets were kept too long in the annealing drum. While in the drum, they became coated with a layer of metal dust which the heat then sintered onto the planchet. These are known with partial, single-sided, and double-sided sintering. See also Copper Wash.
definition from.. DMPLdollar
I've seen (and sold) presidential dollars that came straight from a mint bag that are sintered.
I also have a light lavender colored Peace Medal nickel that is sintered.
I've run across a PCGS AU55 Type 2 Ike that has some dramatic sintering.
As well as a 1978 IKEthat appears to be sintered.
Its the middle coin which shows it hasn't been dipped for chemical alteration.
For the OP, will PCGS cross the coin? I'm thinking yes since darn near anything can cross as long as they determine it has not been chemically altered but I don't think it would retain the Sintered designation.
The name is LEE!
<< <i>Sorry – but that “numis-definition” of sintered is both misleading and metallurgically wrong. Seems like somebody grabbed a sophisticated sounding word and attached it to a mint production error without understanding what the word meant. >>
The "numis-defininition" is not what I am questioning ..The appearance of the coin is the look of sintered.....My question is will PCGS put this coin in it's holder..??
<< <i>Sorry – but that “numis-definition” of sintered is both misleading and metallurgically wrong. Seems like somebody grabbed a sophisticated sounding word and attached it to a mint production error without understanding what the word meant. >>
Seems to me that the definition is right on.
From Wikipedia: Sintering is a method for making objects from powder, by heating the material (below its melting point) until its particles adhere to each other. Sintering is traditionally used for manufacturing ceramic objects, and has also found uses in such fields as powder metallurgy.
The constant movement of planchets through the annealing process causes metal dust or powder to accumulate in the ovens. If a planchet were to get jammed or stuck in the ovens then an unusually large amount or that powder gets adhered to the planchet which causes the darkened appearance.
Perhaps you could expound upon your response?
The name is LEE!
San Diego, CA
<< <i>Sorry – but that “numis-definition” of sintered is both misleading and metallurgically wrong. Seems like somebody grabbed a sophisticated sounding word and attached it to a mint production error without understanding what the word meant. >>
Perhaps, but the error field has other examples of wrong definitions that are used commonly. One is a "clipped" planchet or "clip" which is correctly termed an incomplete planchet. Another is a "lamination" which is more accurately termed a "delamination." A term is used and it gains popularity and ... then you know the rest of the story.
Will that coin cross? Who knows...it depends on whether or not it was actually "sintered" or artificially toned. From the image it is hard to tell and SGS is not known for their specific expertise in mint errors.
Lane
See http://www.doubledimes.com for a free online reference for US twenty-cent pieces
Discolored coins with a black, brown, reddish, or coppery color were originally tagged either "copper wash" or "sintered plating", both labels tied to highly speculative theories. Copper wash refers to the theory that planchets are immersed in a chemical rinse bath that is saturated with copper ions, which then bond to the planchets' surface. Sintered plating refers to the theory that copper dust in the annealing drum adheres to and is baked on to the surface of incoming planchets. Both theories leave much to be desired.
In severe cases, thick layers of copper end up on the surface of copper-nickel and Cu-Ni clad coins. I am not convinced that Sac dollars or Presidental dollars are prone to this sort of error. They may be discolored for other reasons. Some of the heavily plated nickels are significantly underweight, which undermines both the copper wash and sintered plating theories.
As to why copper accumulates at the surface, no one really knows. Do copper atoms segregate out from the Cu-Ni alloy and migrate to the surface? Do nickel atoms segregate out and sink inward, leaving the copper fraction behind? Are nickel atoms liberated from the surface leaving the copper fraction behind? Or are copper atoms liberated from the surface and redeposited as a thin layer? I'm no metallurgist so I don't know. Metallurgists I've consulted don't understand the phenomenon either.
-- Mike Diamond
...and coins are not made that way.
If a few error folks want to contribute to the confusion of new collectors and add to the already sad distortion of language in coin collecting, that is fine. The better way to handle it, is to agree on a term that does describe what occurs. A heretical possibility is to ask the US mint what they call it – after all, the coins were created in their factory and they likely have a very workable and metallurgically correct term for what occurred.
Lastly, if you want the flexibility of "crossing over" error coins from one authentication service to another, maybe you should think about the above.
Anybody remember "FIDOs" and a herd of other error terms that did not properly describe the error, and have been replaced?
Despite the NGC slab, I've neither seen nor heard of any convincing evidence that would link the type of discoloration shown in this slabbed dollar to events transpiring in the annealing drum.
<< <i>"Improperly annealed" is a fine term, at least in the interim, because it is nonspecific as regards the specifics of discoloration and copper deposition.
Despite the NGC slab, I've neither seen nor heard of any convincing evidence that would link the type of discoloration shown in this slabbed dollar to events transpiring in the annealing drum. >>
Try this link.....for all the non believers.....Fred Weinberg link