Decorate cookies. While icing is still wet, place cookie on wax paper. Cover with white sparkling sugar. Pour off excess. Repeat with all cookies. Funnel excess sugar back into bottle for later use.
Place pieces of rock candy in center of cookie, forming a heart shape, about 1/4 in. to 3/8 in. from border.
Mix 1/8 teaspoon burgundy icing color with small amount of lemon extract. Mix 1/8 teaspoon violet icing color with small amount of lemon extract. Using brush, paint random areas of rock candy with burgundy and violet colors.
Prepare decorating bag with piping gel; cut small tip. Pipe gel around center heart and cover with white sparkling sugar or Cake Sparkles.
Mix small amount Bronze Pearl Dust and Brown Color Dust with lemon extract. Using brush, paint edge of cookie border. Let cookies dry 8 to 10 hours.