I have also seen similar centerpieces that use epsom salts instead of sugar. You could also sprinkle a mix of pearls/gems. Sand (or sugar), faux pearls, a 3 candle. An easy DIY wedding centerpiece idea.
Burlap Wedding mason jar Centerpiece - glass jars wedding centerpiece，Rustic Wedding Guestbook pen holder， ivory wedding flower decor ideas another idea would be to embroider initials on the burlap heart for a more personal touch