I had the idea for this set of gemstone cupcakes a while back, and as most just for fun projects go around these parts it took me quite some time to actually make them.  But, they’re finally here…and I couldn’t be happier with how they came out!  For the cupcakes I topped each one with a unique edible gemstone including: an agate slice, a geode, tourmaline, azurite, and pyrite. If you’re interested in making one or all of the gemstone cupcakes, follow along to get the DIY.

Part #1 – The Sugar Base: To make the crystallized base of each cupcake (and the pyrite, tourmaline and azurite crystals), you’ll need to make a hard candy from sugar.  It’s VERY important to use a potholder and to keep a distance from the pot once your sugar mixture gets hot, as it can bubble and may splatter outside of the pan. Before you start, I’d recommend watching some how-to videos on YouTube or google search “sugar burn”, just so you know how serious and frequent sugar burns are.  Use extreme caution, people!

Update – Some Advice: If baking and working with sugar are both uncommon grounds for you, I’d recommend just using pre-made hard candy for the bases and gemstone pieces. You can buy large lollipops, rock candy, or colored hard candy at most grocery stores and all you’ll need to do is break it apart with a hammer (put the candy in a plastic bag and then wrap a dish cloth around the plastic bag before hammering).

What You’ll Need:

• Granulated Sugar
• Light Corn Syrup
• Saucepan + Pot Holder
• Spatula
• Food coloring or gel color
• Silpat or Parchment paper + Pan
• Frosted cupcakes

For each mixture I made I eyeballed the corn syrup and sugar amounts and got the same results each time, so you definitely don’t need an exact ratio for the two ingredients.  I’d recommend using about 2 cup of sugar with 3-4 Tbsp of corn syrup for your first batch. 

First, mix together the sugar and corn syrup in a saucepan. Turn on heat to med-hi, stirring frequently until the sugar starts to dissolve. Once the sugar is dissolved and the mixture begins to boil, stop stirring and allow the mixture to cook for a few minutes.  Once your mixture reaches a light amber color, remove from heat and add a couple drops of your preferred coloring.  Mix well until the color has completely dyed the mixture. [Note: If using a water-based dye, it will cause the heated mixture to sizzle and splatter, so keep a distance and make sure to use a potholder.]

Next, lay a Silpat or parchment paper onto a baking pan. Working quickly, pour your dyed sugar mixture onto the lined pan and place in refrigerator.  [Note: You can also pour the sugar mixture into silicone molds or greased muffin tins to get larger solidified sugar pieces.]

After 15-30 minutes in the refrigerator your candy should be completely hard. You can take a knife, hammer, or you can use your hands to break down the sugar. For the pyrite, tourmaline, and azurite cupcakes, set aside a few larger pieces for the crystals.  To break down the sugar to a fine sugar for each of the cupcake base, you can use a food processor.  Or just place the sugar pieces into a plastic bag, cover with a towel, and hit with a hammer.

For each cupcake, first frost the top with buttercream. Place the colored fine sugar onto a plate and roll the top of the cupcake in the sugar.

Part #2 –  The Gemstone Toppers (materials required are noted in bold)

Green Tourmaline Crystal: Add green dye to your sugar mixture. Once hard, break down sugar, setting aside a few of the larger pieces for the tourmaline crystals that will sit atop the cupcake. Roll cupcake in fine sugar, then position larger pieces into the center. Once you’re finished decorating, set cupcake(s) in the refrigerator to set.

Blue Azurite Crystal: Add blue dye to your sugar mixture. Once hard, break down sugar, setting aside a few of the larger pieces for the azurite crystals that will sit atop the cupcake. Roll cupcake in fine sugar, then position larger pieces into the center. Once you’re finished decorating, set cupcake(s) in the refrigerator to set.

Metallic Pyrite: Do not add any coloring to your sugar mixture. Once hard, break down sugar, setting aside a few of the larger pieces for the pyrite pieces that will sit atop the cupcake. Roll cupcake in fine sugar, then position larger pieces into the center. Use a paintbrush to apply either an edible metallic color (i.e. AmeriColor airbrush color) or a gold decorating dust. Using a paintbrush, cover the entire crystals and the sugar base with the metallic color. Once you’re finished decorating, set cupcake(s) in the refrigerator to set. [Note: Pyrite is typically a silver-gold metallic, but since I only had gold, that’s what I went with. If you have the gold and silver metallic colors, get wild and use them both!]

Geode: First roll out two pieces of fondant – one marbleized gray and the other white. You can achieve the marbleized gray color by mixing a few small pieces of black fondant into white fondant. Once you’ve rolled out the two layers, lightly moisten the top of the gray piece with water and adhere the white piece of fondant on top.

Line a bowl (or a silicone mold) with tinfoil. Use multiple pieces of foil to make a rock mold. Lightly grease the tinfoil using cooking spray and lay your fondant into the tinfoil mold.

For the crystallized interior of the geode, you’ll need to cook a saturated sugar mixture. In a saucepan over med-hi heat, mix 3 cups of sugar and 1 cup of water until dissolved (completely clear). Remove from heat and add your desired dye color.  Set aside to cool for 1-2 minutes, then pour directly into your fondant mold. Cover the entire mold and bowl with tinfoil or plastic wrap and set aside to crystallize for 12 to 16 hours.

The next day, break through the top of the sugar with your finger. Pour out the liquid that has not crystallized. Set aside to dry for a few minutes. Once your geode’s interior is completely dry you can take off the tinfoil, trim the edges of your fondant mold, and cut to size/shape of a geode. Once happy with the shape, position atop a sugar coated cupcake.

Update – Some Advice: There’s a video on YouTube from HowToCookThat that demonstrates a how-to for the geode process – watch that HERE.

Agate Slice: Roll out a small ball of white fondant and cut/shape to resemble a rock slice. [Note: Feel free to use a cookie in place of the fondant]

Prepare two batches of royal icing – leave one white and dye the other a color of your choice. Working from the center, add rings of royal icing, alternating the colors. You can also add darker tones by using a toothpick and adding a bit of the dye color you used for your frosting. Once you reach the edge, you can leave as is or you can add additional detail around the edge.  I used a touch of metallic airbrush color around the edge of my slice to add a bit more dimension. Let royal icing completely set before placing atop your cupcake.

Update – Some Advice: Check out the Agate Slice Cookie DIY for additional help. You could even swap out that fondant with a mini cookie, if you prefer!