coinexamining-88

“What to Look for When Examining a Coin”; Robert A. Izydore Raleigh Coin Club Newsletter,
January 12, 1988.

1. technical grade of the coin. The condition or state of wear of a coin.
2. amount of mint luster. Dull, satiny, or frosty shine found on well preserved coins. If a coin has full
mint luster, it is uncirculated.
3. quality of the strike
4. bag marks (looks shiny)
5. extent of and attractiveness of toning
6. artificial toning
7. corrosion or pitting
8. carbon spots
9. finger prints
10. evidence of cleaning
    a. mechanical: polishing, rubbing with a cloth, etc. This is readily detected under
        magnification as hairlines in the protected as well as the unprotected areas of the coin.
    b. chemical dipping: If skillfully done, dipping won't leave hairlines, but the color of the
        coin may not appear natural.
11. whizzing: The surface of the coin is altered with a stiff wire brush, usually in a circular motion
        in order to simulate the appearance of mint luster.
12. die polishing
13. die radials: Small erosion lines which radiate from the center of a coin toward the edges. As
        coins are struck the die faces gradually erode as metal is squeezed outward toward the
        collar which holds the planchet. The term flow lines is sometimes used.
14. scratches
15. damage to the edges and rim
16. dents, digs, nicks, gouges, etc.
17. plugs and other repairs
18. bending of the planchet
19. adjustment marks. These are dull and not shiny if done at the mint.
20. die scratches. These appear as raised lines on the surface, and are the result of a crack in the
        steel on the face of the die.
21. die cracks. These result as the dies becomes damaged after extensive use and are raised
        above the surface of the coin.
22. die breaks or cuds. A piece of the die face had broken off, resulting in a raised blank area on
        the coin.
23. lamination: A defect caused by splitting or layering of a coin.
24. doubling (machine doubling, doubled dies, etc.)
25. varieties
26. overdates, over mint marks, etc.
27. re-engraved dates
28. clash marks: A reversed, incused design detail imparted on a coin struck from dies which
        previously had been struck together when there was no planchet between them.
29. struck from rusted dies
30. struck through grease, lint, etc.
31. business strike vs proof
32. mint errors
33. authentic or counterfeit