Make rings two days in advance. Tint 6 oz. fondant gray. Knead 1/2 teaspoon of Gum-Tex into gray fondant.
For rings, use gray fondant jewelry fondant and gum paste mold to mold mesh, chain link or square chain border to make 24 bands. Unmold according to package directions. For mesh border, use ruler and fondant trimmer to cut only two rows of dots. For each ring, use trimmer to cut, 2 3/4 in. long.
Use cornstarch-dusted dowel rod to wrap rings around. Use lightly dampened brush to secure ends together. Lightly press together and flatten slightly where gem will sit. Keep flat to dry overnight.
For gem backs, use gray fondant and jewelry fondant and gum paste mold to make eight of each ring setting. Unmold according to package directions. Let dry overnight.
For gems, tint 3/8 in. ball of fondant each kelly green, royal blue, red, sky blue, rose, topaz, violet and peridot. Reserve some white. Use jewelry fondant and gum paste mold to make eight each round, square and gems. Unmold according to package directions. Let dry overnight.
Assemble rings one day in advance. Use silver Pearl Dust/lemon extract mixture and brush to paint all rings and settings. Once dry, brush with dry silver Pearl Dust.
Use matching color Pearl Dust/lemon extract mixture and brush to paint all gems. For light colored gems, brush with white Pearl Dust.
Prepare gum glue adhesive following recipe directions. Use brush and gum glue adhesive to attach gems to backs and then backs to band. Let dry overnight.
Make cupcakes. Prepare batter following recipe directions. Bake and cool cupcakes.
Prepare buttercream icing following recipe directions. Use spatula and icing to ice tops of cupcakes smooth.
Assemble cupcakes. Press rings in center of cupcakes. Place cupcakes on stand.