Preheat the oven to 350 degrees F. With an electric mixer, cream the butter, sugar, vanilla, and salt until smooth. Scrape the bowl with a spatula. Turn the mixer on low and add the flour a little at a time, until it is just combined.
Cover and chill the dough for at least 30 minutes. Line your cookie sheets with parchment paper. Roll the dough into 1-inch balls.
Place the balls on the cookie sheets 3 inches apart. Make a deep indention in each cookie, with your thumb. Press any cracks back into place.
Spoon a scant 1/3 teaspoon of cherry preserves in the center of each cookie. Bake for approximately 20 minutes.
While the thumbprint cookies are still warm, press a few pieces of crystallized ginger into the cherry center of each cookie and sprinkle with gold shimmer sugar.