Readers Ask column from May 16, 2016, Weekly issue of Coin World:

The reason for my message is to get some information about the Type 2 1981-S Proof set. Are all of the six coins in the Proof set required to have the Type Two S Mint mark in order for it to be called a Type 2 set? It may sound like a dumb question, but I have seen mixed information published in various sources about this set. If it is not required for all six, then what is the requirement? 

Mario Difede  /  Via Email

In order for the 1981-S Proof set to be considered a Type 2 set, the S Mint mark on each of the set’s six coins — Lincoln cent, Jefferson 5-cent coin, Roosevelt dime, Washington quarter dollar, Kennedy half dollar, and Susan B. Anthony dollar — must be of the Type 2 style.

Finding an intact Type 2 set still in its original Mint packaging is not the easiest of tasks. Some sets were issued with a mix of Type 1 and Type 2 coins, and some with all Type 1.

Many sets offered as Type 2 that have each coin individually graded and encapsulated by a third-party grading service may contain coins culled from multiple sets. 

One can pay hundreds or even thousands of dollars for certified Type 2 coins depending on denomination and grade, with the Kennedy half dollar being the rarest Type 2 coin among the six denominations.

Because less than 10 percent of the more than 4 million 1981-S Proof set coins struck bear the Type 2 Mint mark, those individual coins are valued at and sell for hundreds of dollars each higher than their Type 1 counterparts.

What is referred to as the Proof 1981-S Type 1 Mint mark (the more common of the two Mint marks for 1981-S Proof coins) was first introduced in late 1979 for that year’s Proof coins. The serifs on the S are small, the relief is rounded and the center loops of the S are oval.

Late in 1981, the Type 2 Mint mark was introduced. The serifs are larger, more bulbous, with flat relief. The two loops in the letter S are also circular.