The tiny, early American silver coin personally authorized by President George Washington 215 years ago, and purchased for a headline-generating record $1.5 million this past summer by a Sunnyvale educational foundation, will make its first Northern California public appearance.

The finest known 1792 half disme, recently purchased for $1.5 million, will be displayed for three days at the four-day Santa Clara Coin, Stamp and Collectibles Expo Nov. 1-3.

The Whitman Coin and Collectibles Atlanta Expo includes an exhibit of a unique gold coin valued at $2.5 million, sold-out dealer booths and two auctions.