RWB

Modern coin sculptor/engravers don't seem to pay much attention, except on medals. Properly basining and polishing items such as the baseball commemorative remain a problem for the US Mint. Other countries don't seem to have so much difficulty -- or at least they don't harp on it. Independent sculptors use various textures. including mirrors, for their dramatic and artistic effects, so it's not so much of an overall objection as it once was.

I [say your name] do solemnly swear [or “affirm”] that I shall not watch another U-Tube video about error coins; and further, I shall not claim that a coin run over by a dump truck is a “mint error worth thousands,” so help me God.

I am not aware of any sculptors or medallic artists who favored mirror-like polish on medals or coins. All felt it was cheap and suitable only for tawdry tokens and baubles. From a manufacturing position, it was difficult to give a uniform polish to irregularly curved surfaces, as were normal on medals. Engravers at the Philadelphia Mint were fully aware of this, but also did what they were told and followed tradition. Coin collectors favored polished fields on master and proof coins; this gave the pieces a distinctive appearance that was not available with satin, matte or sandblast surfaces.

Damage and circulation - nothing more.

Very nice example of this variety!

Excellent presentation by Dr. Khachatur Manukyan is a Research Associate Professor at the Nuclear Science Laboratory in the Department of Physics and Astronomy at the University of Notre Dame. Available on the American Philosophical Society. "If you are joining us remotely, you can follow the program through our live stream. If you can not tune in at 6 pm, the stream can be played back at a later time. "

Use a standard oven thermometer and when the temp is a little over120F, turn the oven off and put in your silica gel. (No need to baste, rotate, turn, braise, or broil.)

Please stop looking at U-tube videos about coin errors. Almost all are lies and gross exaggerations. Members here will help you in any way they can. They will not lie to you, although they might occasionally disagree among themselves.

PS: Humidity is nasty stuff for coins. Suggest you rotate packets so your coins are not left unprotected for even a few hours. (At the old New Orleans Mint rust prevention required constant attention. If you are looking for coins made from "rusted dies," NO is the place to look.)

Here's my little contribution to the discussion:

The "traditional" die varieties have only been loosely linked to proof 1921s. There are many more characteristics required to confirm that a coin is a 1921 proof dollar, but the superficial observations are a useful start. None of the TPGs tell collectors how they make a determination. The whole subject needs thorough and objective examination by multiple people.

The usable life of silica gel (aka, silica xerogel) depends on the humidity and air circulation. The best commercial products have an indicator added so the material turns blue when it's saturated. You'll have to test for longevity. In a humid place, such as the Gulf Coast, you might have to replace every month. I am not familiar with any specific brand -- you'll have to read the labels. Hardware stores and some coin shops carry silica gel. You can regenerate it by gently heating to about 120F for a couple of hours.

Put silica gel packets and sulfur absorbent with your coins in a closed box. Change both absorbents regularly.

For bare coins, tarnish and surfaces are best controlled with low humidity, low oxygen exposure, no added contaminants, and moderate temperature --- 20-degrees C being the standard. This is close to powermad5000's tool gangbox example. Ideal might be positive pressure helium/argon atmosphere with 0% humidity, low light and no exposure to packaging out-gases. Geographically, look for areas away from moisture, especially the ocean or large body of water, or humid conditions; areas away from coal, natural gas or processing facilities (sulfur), chemical manufacturing, and so forth.

Please explain: planchet annealing; thickness of CuNi layer; what is meant be "stressed" and "not properly adhered"; what is "exchange copper" ? Be as technical as you wish.

Stacks-Bowers sold a MS-67 quarter, the likely condition when shipped to Mr. Raymor (above), for $9,600. Heritage sold a MS-67 half dollar for $20,700 in 2008, and a proof 1888 gold dollar for $15,750. If kept together and in original condition, you can figure the final present value.

Coins and their packaging or holders might require different "ideal" storage conditions. It's likely to vary with protection vs prevention.

More -- Zinc plating (or hot dipped) was nasty stuff. It routinely clogged dies, and the Engraving dept resorted to having dies chromium plated by the Bureau of Standards in Washington to reduce sticking. The areas near cent presses were coated with a fine layer of zinc dust, causing complaints from workers and the necessity of daily cleaning. The volatility of zinc used in brass ammunition cartridges, forced the 1944-47 mints to have the cartridges melted by contractors rather than at the mints as originally planned. Resulting brass ingots were then remelted at the mints and "sweetened" with pure copper until the correct normal alloy was achieved.

This is one of many letters to a collector who ordered uncirculated silver coins from the Philadelphia Mint. RG104 E-6 Box 29 Vol 3 June 16, 1888-Mar 2, 1889 December 29, 1888 Sir, I send you by Adams Express, 2 Silver proof sets $6.00 5 Minor proof sets .60 5 Gold proof dollars 6.25 2 Three [dollar] proof 6.50 6 Uncirculated half dollars 3.00 6 Uncirculated quar dollars 3.00 11 Uncirculated dimes 1.10 and 5¢ change .05 $25.00 as requested. Very Respectfully D. M. Fox, Superintendent Mr. Isador Raymor Baltimore, Md

He was also a pernicious liar and fraud. Much of the quoted section is invention and distortion, and the rest is false. He and his ilk sold emotional trauma and insecurity; the same breed of honesty thug proliferate on-line and in phony "news" sites.

These silver tetradrachm are sold at highly inflated prices because of completely unsubstantiated speculation about their payment to a disciple of Yashua ibn Yousif in exchange for Yashua's whereabouts near Jerusalem on Passover evening. There are, in my view, many more interesting and historically valuable coins of that era.

Any coin with three obverses and only one reverse is valuable.... Especially if all are from fuzzy dies. Seriously, Sandon provided good value information.

Your dime looks nicer than most other impaired coins of similar grade. It's not valuable enough to have graded and put into a plastic slab, but you might be able to get $50+ from a date/mint Barber dime collector. Might be a nice ebay coin.

No numismatic value.