Frank Steele wasn't exactly dying to come to Washington, and Moe Parzow had no great love for Philadelphia. So one Sunday this spring, the two men, who had never met, agreed to a rendezvous halfway between their home towns, at the I-95 offramp in Rising Sun, Md.

They chatted for perhaps 20 minutes about the Washington liquor business (Parzow's) and the Philadelphia real estate business (Steele's). Then it was time for the real business.

Parzow reached into the glove compartment of his car. Steele reached into his wallet. As Steele handed over a fat wad of crisp 20s, Parzow handed over a plastic case containing the Moose McCormick Medallion.

As jewelry goes, the Moose Medallion does not have half the notoriety of, say, the Hope Diamond. But it carries with it a rather epic story - of a baseball player apparently down on his luck, of an old Washington pawn-broker who played it cagey, of a chance purchase by his son-in-law. And of a fanatic baseball memorabilia collector who knew a good thing when he heard about it.

It all begins with Harry Elwood McCormick, who as dubbed Moose as a young man because, in his era, being 5-feet-11 and 180 pounds was considered mooselike.

McCormick batted left, threw left and spent 10 seasons in the big leagues just after the turn of the century, most of them with the New York Giants. He mainly became two things: a drinking buddy of the Giants' legendary manager, John McGraw, and an excellent pinch hitter.

"If there were a special Hall of Fame category for pinch hitters," wrote the Hall's former director, Ken smith, in 1971, "McCormick would be perhaps the first that would come to mind for membership."

McCormick's most memorable season was 1908, when he batted .302 for the Giants (including six game-winning pinch hits) and became a darling of the New York fans and press. Riding Moose's wave, his fan club presented him with a gold medallion, inlaid with a six-point diamond. The medallion bore McCormick's and the Giants' names, and the ringing phrase, "A Tribute From The Fans."

It might have been 10 years later that Moose walked into William Tenn's pawnshop at Georgia Avenue and Irving Street NW, six blocks from Griffith Stadium, where the Senators used to play. Then again, it might have been five years later or 15 years later. Tenn, now 90 and ill, cannot recall.

Nor does he recall whether Moose looked seedy, hung over or desperate that day, or whether it was a Senators game that might have brought him to the neighborhood.

What Tenn does recall, according to Moe Parzow, his son-in-law, is what he paid McCormick for the medallion.

Three bucks. Take it or leave it.

The long and the short of it was that Moose got stiffed. As Parzow notes, "Just the two ounces of gold in the medal alone was worth about 10 times that much."

But McCormick took his $3 and never came back for the medallion. Tenn never had a nibble from another buyer. The Moose Medallion sat in his pawnshop safe for nearly half a century, until the shop was condemned in 1968 and he decided to retire.

Parzow found the medallion as he was helping his father-in-law clean out the place for the final time.

"I liked baseball, sure, but I had no idea who McCormick was," says Parzow, 60, now a counterman for Colonial Liquors at 20th and M streets NW. "I just looked at the medal and thought it was pretty. I decided to buy it for my wife. I paid him $40 for it."

Parzow's wife put the medallion on a chain and started wearing it on dress-up occasions. Naturally, people noticed, and one friend guessed that she could sell it to the Hall of Fame. The Hall of Fame wasn't interested (no budget), but they knew someone who might be: Moose's daughter, Maria Billhardt, in Manhasset, N.Y.

Parzow's son Howard, 30, a Washington auctioneer, visited Billhardt in 1975, but they could not agree on a price. The Parzows kept writing Billhardt with revised offers, but she stopped replying.

Then, this spring, at an auction in Totowa, N.J., Howard Parzow was telling a friend about the medallion. Steele, who was there hunting up baseball artifacts, overheard. A month later came the great exchange beside a freeway.

The exchangers do not agree on the selling price, and do not want it published. Suffice it to say that it was many hundreds - and as they always say in baseball, both sides think they got the better of the deal.

Steele and his wife have a baseball collection that fills "every room of our house. I may have to buy a warehouse one of these days." Still, said Steele, the McCormick Medallion is "so one-of-a-kind" that it has gotten a display site of honor: Steele's desk.

McCormick was "not a pivotal figure in baseball history, but he did have one hell of a year (in 1908)," Steele explained. "I saw the pictures of the medal, and in hit us in the belly button, so, hell, I bought it."

And Steele plans to keep it, although not for any half century.

"I might trade it. And I could sell it tomorrow for a reasonable profit. But it's here until it's not here," he said.

So after 60 years in Washington, 50 of them in suspended animation, the Moose McCormick Medallion - and its mystique - have moved on up the road.

Moe Parzow says he regrets never having seen the Moose play. "They gave him that medallion. He must have been something," Parzow said.

William Tenn told his family the other day that he was sorry he didn't realize what he had all those years. If he had, the old pawnbroker said, he would have at least tried to make a profit.

Meanwhile, Frank Steele says he has become so interested in McCormick's career that he is hunting other Moose trinkets.

And Moose himself? He died in Lewisburg, Pa., in 1962 - without ever explaining why he sold his medallion in a strange city two generations before. CAPTION: Picture, Harry Elwood McCormick in 1903 when he was playing for the Jersey City team of the Eastern League and the medallion presented to him by his fans when he played for the New York Giants in 1908.