Gold Mercury dimes, Standing Liberty quarters and Walking Liberty half dollars are another step closer to reality.

The Mint posted a press release on its website yesterday that featured some of the details of the coins that will commemorate the centennial of the introduction of the three designs in 1916.

All of them will be struck in .9999 fine gold, matching the purity of the American Buffalo gold bullion coin.

Purity of the American Eagle gold coins is .9167, which is the old British standard later adopted by the South African Krugerrand.

The commemoratives will be struck in even troy weights, tenth ounce, quarter ounce and half ounce, respectively.

I doubt that greater purity of the gold will be on the minds of collectors who seem set to go wild over these special coins. But it might be of importance later.

Will these become the beginning of a new bullion coin series for the Far East?

Asian buyers prefer the .9999 fineness to the lower quality of gold in American Eagles.

What might they think of fractional ounce sizes with these classic U.S. coin designs on them?

The Buffalo set had fractionals issued in 2008, but they lasted just a year as the Mint had difficulty supplying the bullion coins investors were demanding, which basically meant the Eagles.

While Buffalo fractionals might be considered a failure, it was simply a Mint response to the huge leaps in demand for American Eagles. Resources logically were concentrated in the biggest markets.

Perhaps it is time to try the .9999 fine bullion coin market again after the initial offerings to collectors.

There is no reason why the fractionals would have to have matching Buffalo designs on them.

Of course, this would be another tumble down the slippery slope of proliferation, but we fell off the promontory long ago.

What’s one more program?

The classic designs will be modified with the inclusion of “AU,” “24K” on each of them and the weights, “1/10 OZ,” “1/4 OZ.” and “1/2 OZ.,” respectively.

If these coins are to be strictly commemoratives to be offered only to collectors, indicators of weight, fineness and purity are not really necessary.

The Mint has not yet set sales dates or mintage figures for the commemoratives. And, of course, pricing will be determined as close to the issue date as possible to prevent market swings from disrupting the program.

With .85 ounces of gold in the three coins, we know that the bullion value alone at today’s gold price is $925.

Add the 37 percent mark-up the Mint usually charges and we are in round numbers at $1,265.

This is the baseline.

Prices might be higher.

If gold drops significantly, prices could also be lower.

What will not change is the popularity of these three classic designs.

Buzz blogger Dave Harper has twice won the Numismatic Literary Guild Award for Best Blog and is editor of the weekly newspaper "Numismatic News."

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