NGC Error Coins & Mint Varieties 3

Question 1

What is a 'cud' on an error coin?

Accepted Answer

A raised lump of metal at the rim area caused by metal flowing into a die break that extends to the edge

Answer

A depression in the coin's surface caused by a foreign material strike-through

Answer

An unstruck flat area on the coin resulting from die misalignment

Answer

A tool mark transferred from the die that appears as a raised blob in the design field

Question 2

An 'overmintmark' (OMM) variety is created when:

Accepted Answer

One mintmark punch is applied over a previously punched mintmark letter of a different mint

Answer

A mintmark is punched too deeply into the die, creating an exaggerated sunken appearance

Answer

A mintmark is inadvertently placed in the wrong location on the working die

Answer

A mintmark is only partially visible because the punch did not fully enter the die

Question 3

What characteristic most distinguishes a proof die from a business strike die?

Accepted Answer

Proof dies are polished to create mirror-like fields that contrast with frosted, sandblasted design elements

Answer

Proof dies are manufactured from a harder steel alloy specifically formulated for polishing resistance

Answer

Proof dies are reserved exclusively for gold and platinum commemorative coinage

Answer

Proof dies strike coins with significantly greater tonnage than standard business strike dies

Question 4

A 'flip-over double strike' error occurs when:

Accepted Answer

A coin is turned over and fed back through the press, so both faces show design elements from both sides superimposed

Answer

Both sides of the coin show identical doubling from hub movement during die creation

Answer

The reverse die flips orientation during the production run causing misalignment

Answer

The coin is struck twice in succession with the die rotating exactly 180 degrees between strikes

Question 5

In variety collecting, the abbreviation 'RPM' stands for:

Accepted Answer

Repunched Mintmark, where a mintmark was punched more than once into the die at slightly different positions

Answer

Revised Planchet Method used in die preparation

Answer

Rotated Press Mechanism causing misalignment errors

Answer

Repositioned Proof Mark added during the encapsulation process

Question 6

The organization CONECA is primarily dedicated to:

Accepted Answer

The research, cataloging, and study of mint error coins and die varieties

Answer

Authenticating and certifying ancient and medieval coinage for U.S. collectors

Answer

Setting professional grading standards and encapsulation protocols for the industry

Answer

Promoting transparency and best practices in numismatic auction markets

Question 7

A 'die crack' produces which visual characteristic on a struck coin?

Accepted Answer

A raised irregular line on the coin's surface caused by metal from the planchet filling a crack in the die during striking

Answer

A recessed irregular line running across the coin's surface from a planchet crack

Answer

A flat unstruck area where the cracked section of the die failed to make full contact with the planchet

Answer

A deliberate groove added to the die design by the engraver as a security feature