How to Make DIY Resin Geodes

The first thing I needed to do was to make some wooden bases in the shapes that I wanted the finished geodes to be.
I did a quick design in illustrator and while I was at it I made a mix of shapes and sizes because I figured I might as well make a coordinating cluster instead of just one. After I had the file the way I wanted it I cut them on our big Laguna EX laser cutter, however you could easily do this with a scroll saw, a band saw, a cnc router, or even hand tools. They’re supposed to be organically shaped which makes it especially simple to get something that looks realistic.

Once I finished cutting out the geode blanks I used painter’s tape to create a border around the edge of each wooden piece. It is really important to firmly fold and press the tape onto the back of the wood; to minimize leaking.

Additionally, I am putting a whole layer of painter’s tape on the bottom edge as well to make things even more secure. At this point it is also really important to line the surface where you are doing your pour with silicone, plastic, or anything that resin will not soak through to protect your work surfaces.

After thinking through my options I decided to use pigments to color the resin because it is nice and opaque and will keep the wood from peeking through. Before deciding on colors I dug through our entire stash of mica powders and other pigments. I figured going monochromatic would make for a striking finished piece so I started with a black and white geode. For the black I used charcoal powder, which makes for a fantastic deep black in resin, while being affordable and easy to come by. I also added a little metallic grey and a metallic pearl mica powder to give it a little shimmer.

Before mixing my resin I portioned out my pigments into small paper dixie cups.
Then I mixed up the resin. I am using total boat 2:1 with a medium hardener for this because it’s a nice shallow pour, and this resin will start thickening pretty quickly which in this case will minimize leaking since this is only sealed with painter’s tape. It’s important to mix resin exactly as  the packaging specifies for it to cure properly.

I made one large batch and then divided it up amongst the smaller cups that I had previously put the pigments in. After mixing them thoroughly I went in for the pour.

I started with the lightest color on the interior of the geode, and got progressively darker as I got to the outer rings. Ombre is a really easy way to make dimension and also a really easy fool-proof way to avoid muddiness.
After pouring I started dragging a zip tie through the mixture to start blending my colors and was decently impressed with how that looked before blowing through a straw to finish blending. I mostly blended with the straw, primarily just because it was fun. However, there’s really no right or wrong way to go about blending the colors.

I ended up blending it a little too much on one side, and in the 11th hour decided to toss some color in which was a mistake. No matter how many times I do resin pours I need to remind myself often to stick with the original concept and to know when to stop.

Next I went in for the big geode. I wanted this one to be royal blue, and again stuck with one color family; I thought that would be the most striking.

This was a lot of fun because once I was set up I could really settle into letting myself decompress and enjoy the process; it’s kind of meditative, you know?

I added a mix of crushed up clear crystals and mirrored chips towards the center of this one for texture and sparkle. I’ll link exactly what I used in the info section of the post. They worked out tremendously well, and to be honest looked even better than I thought they would.

I wasn’t planning on it but on a whim went ahead and made the rest of the geodes in the same batch. I did a monochromatic green one, and also a purple one.

One the green geode I mixed it up a bit and blended primarily with a heat gun. An easy substitute for this is a hair dryer if you don’t have a heat gun kicking around. However you want to be careful to not get any wet resin on it (oops).

After letting the resin completely set up so it was hard to the touch I peeled off the painter’s tape. It comes off relatively easily, but can stick a bit in tight corners. I tactfully used blue tape with the blue geode, and green tape with the green geode so that if there was any that stuck behind it would blend in a little better.

The edge of the resin can be quite sharp and there’s a range of ways to handle this. I found it easiest to sand it down carefully, being careful not to scuff up the surface.

Then I filled the hole in the center of the big blue one with some larger crystals that I had found on amazon. I will also link these in the info section of the post. I used hot glue for most of this in addition to some super glue gel because it was easier for the smaller crystals on the green geode.

Since the first geode was my least favorite I used a metallic paint to cover the edge before deciding that I thought it would look cooler if I painted it black; one of the benefits of having a token “ugly one” is that I could use it as a test subject.

I happened to have a black nail polish kicking around and on a whim thought it would look perfect. I tested it on my test geode and it blended perfectly, both in color, texture, and gloss.

So I went ahead and used it to finish off the edges of all of them.
I kind of liked the bumpy edge that the tape leaves behind because it looked nice and rock like to me; it can be sanded down more however. I wanted to get a shot of the bumpiest of all the edges with the nail polish over it to show just how well this finishing method blended with the resin pour. If you try using nail polish as a finish remember; the more coats of polish, the glossier it will be.

Once the polish dried the geodes were finished!

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