baked goods, diy desserts, diy projects

DIY: Agate Cookies

I wanted to take the agate slice cupcake from my Gemstone Cupcake DIY one step further, so I decided to make a batch of agate sugar cookies. Best of all, I simplified the process I used in the cupcake DIY to make it even easier to do. Follow along below for the DIY!

Agate CookiesAgate Cookies Blue Stone Cut CookiesMaterials Needed:

  • Sugar cookie dough
  • Royal icing (in a piping bag) [for recipe, see HERE]
  • Food coloring (either water or gel-based)
  • Paintbrush
  • Piece of scratch paper
  • Optional: Metallic silver edible color, sanding sugar

Agate Cookies MaterialsDirections: 

Agate Cookie DIY

Step #1: First, roll your sugar cookie dough into small oval rounds and place on an ungreased cookie sheet. Bake your sugar cookies at 350 degrees until the edges are ever so slightly golden brown (about 10 minutes). Once baked, set aside to cool.

Step #2: Once your cookies have cooled (and while they are still soft) gently tear off the edges to create a rough edge around the cookie. If your cookies are a bit uneven (as mine were), use the backside of the cookie as your canvas for Step #4.

Step #3: Prep your gel colors by mixing a small drop of each color with water. You can play around and add more dye or more water to get different shades of each color. I used an egg carton to hold my colors, but if you don’t have one handy, just use individual bowls.

Cookie Workspace

Step #4: Prep your workspace setting out the mixed colors, icing bag, and a piece of scratch paper (which you can use to blot color off your brush). To begin, cut a small tip off of your icing bag. Starting in the center of your cookie, add frosting while working in a circular motion; work until you’re halfway to the edge.

Step #5: Dip your paintbrush into one of your colors and paint the center of the cookie, as well as 1 (or more) outer rings. I prefer to follow the circular pattern of most agates, but feel free to mix it up…just have fun with it! You can water down your brush to get lighter shades of the color in the different rings. Allow the cookie to set for a few minutes. (Note: Working in two parts, prevents any over-mixing and helps avoid the colors from running)

Remember: Make sure to blot your brush to avoid watering down the icing.

Blotting Paper

Step #6: Add the remaining icing around your cookie until you reach the edge. Again, paint using different tones of the color, while following the same circular motion. Set aside to dry. Once the cookies have set for 30 minutes gently paint around the edge using a silver metallic color to achieve the outer appearance of a rock. You can also add sanding sugar to provide a bit more dimension to the cookie. Once you’ve painted the edge, set aside to dry for 24 hours.

Wait a minute…24 hours?!  Yeah, annoying, I know.  But if you’re just wanting to eat them or serve them straight off the plate you certainly don’t need to wait that long. However, if you’ll be transporting these or want to make sure the icing doesn’t crack, you will need to wait the full 24 hours.  Some recommend leaving cookies frosted with royal icing out in the air for the 24 hours, but I always just put mine in a container with a layer of plastic wrap over the top while they harden. And don’t you worry, I promise they’ll be worth the wait!

Agate SlicesAgates Cookies

  1. Jessica

    March 13, 2015 at 4:22 am

    These are beyond amazing! I had to do a double take as they look the real deal!

  2. Jasmin

    March 18, 2015 at 8:03 am

    Loveeeeeeeeeeee!! Ahhhh!!!!

  3. Chloe

    May 27, 2015 at 12:49 pm

    Ahhh I’ve just found your blog!! and I’m obsessed! I can’t wait to show my mum and sister your cake ideas!!

  4. Rebecca Blake

    June 9, 2015 at 3:36 pm

    Beautiful works of art!


    September 6, 2015 at 6:50 pm

    […] See how to make them here. […]

  6. beth

    September 6, 2015 at 11:58 pm

    Amazing! I have an artist/jeweler friend for whom these would be perfect. Do I correctly understand that you are painting the gel colors directly onto wet Royal Icing?

  7. Kelly

    September 10, 2015 at 2:43 pm

    I am a geology major and a baking enthusiasts, these will be the main dish at my graduation party this spring!

  8. Recurring Favs & Hosting Brunch | Weekly Favs & Finds |

    December 18, 2015 at 1:14 pm

    […] I am obsessed with these DIY Agate Cookies by Alana Jones – I can’t get over how beautiful they are, they don’t look real. […]

  9. Agate cookies - food craft ideas

    January 6, 2016 at 8:21 am

    […] jaw-dropping agate cookies from Alana Jones-Mann are some of the most gorgeous I’ve ever seen. Find the step-by-step tutorial on her […]

  10. jessieflo

    January 15, 2016 at 3:00 am

    uuuuuuuhmazing! I am set to make the wedding cake for two good friends who are geologists. Love this idea!!


    February 26, 2016 at 4:32 am

    […] first pick was Alana’s incredible Agate cookies.  These beauties are so pretty, you almost don’t want to eat them. Hand painted, and dusted […]

  12. Agate Cookies – Edible Crafts

    April 7, 2016 at 10:00 am

    […] here on Alana Jones-Mann for the recipe and […]

  13. j9999

    April 18, 2016 at 4:29 pm

    I made the recipe and it was so easy and the cookies came out incredible. They looked so real when the icing was fresh and shiny! 24 hours later when the icing dried, they looked less realistic but not a huge deal.

    If you know any way to have the cookie dry and stay shiny thats ideal!

  14. Nutmeg

    June 8, 2016 at 2:40 pm

    Question – do you paint the wet royal icing or let it dry first? If wet, won’t the brush leave stroke marks?

  15. Meagan

    July 5, 2016 at 10:47 am

    Do you know if these would hold up in the freezer after they’ve already been baked and decorated and left out for the whole 24 hours?


    July 20, 2016 at 7:10 am

    […] favourite projects include some of our favourites too, her famous cactus cupcakes, agate slice cookies and gemstone cupcakes.  The agate cookies in particular fascinate us!  They are completely hand […]

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