This gorgeous DIY gem mirror is a fairly straightforward project that you can knock out in an afternoon. The end result provides a beautiful modern geometric aesthetic that adds style and interest to any space. It’s such a showstopper that you could easily position it above your mantel, which is typically a focal point of the living room, and it would be a gorgeous feature piece…that you made yourself…on a small budget.
Note: The author is an experienced, although not professional, DIY enthusiast. Neither the author nor Homedit is responsible for any injury or damage caused as a result of following this tutorial.
DIY Level: Intermediate
- 24” x 36” flat (non-beveled edges) mirror (Note: Actually, you can use any size of mirror you’d like. Adjust measurements shown in this tutorial accordingly.)
- Glass cutting tool
- Metal ruler
- Fine-tip permanent marker
- Razor blade (e.g., X-acto)
- Clear contact paper
- Metallic spray paint
- Fine grit sandpaper
- Gloves (optional; for working with the glass after it’s been cut)
- Clear-coat spray paint (optional; this tutorial did not use it)
Begin by squaring off your mirror. Mark 24” on both long edges of your mirror, then draw a straight line across. Tip: Use a fine-tip black permanent marker; it will wash off your mirror easily. The washable marker shown in this photo was difficult to see, so I immediately switched it out for a black permanent one.
Place the scoring wheel of your glass cutter on your line, then align the edge of your ruler with the outer edge of your cutter tip. Tip: There is a small gap between the edge of your tool and the scoring wheel, so if you lay your ruler down first, your scored line will be about 1/16” off your marked line. Holding the ruler securely, run your scoring tool from one end of the mirror to the other, being careful to keep the scoring tool’s tip right next to the ruler. (It has a tendency to drift away from the ruler if you’re not careful.)
You only need to score once. Move your mirror to the edge of your worktable. Hold the mirror onto the table with one hand, then with the other hand, grip the smaller (scored) section. With one swift, strong movement, push your arm gripping the smaller section straight down toward the floor. You will hear a snap and see a straight cut right where you scored the mirror. Tip: Some tiny glass shards will fall as you do this, so I recommend laying a large piece of cardboard or something underneath to catch these. (Tutorial for creating your own ombre abstract art, as reflected in this mirror, found here.)
Now that your mirror is square, it’s time to turn it into an octagon. For a 24” square, each side of the octagon will be just slightly less than 10” – so slightly, in fact, that I simply measured 10” sections in the exact middle of each side of the mirror by centering my 24” metal ruler and marking at the 7” and 17” positions.
Mark on the very top edge of your mirror, because this is the point you’ll be aiming for as you create your diagonal lines (for the angled octagon sides).
Once you’ve marked your 10” sides, draw diagonal lines across each corner. These lines should be close to 10” as well. If you find that, for some reason, they are longer or shorter than 10”, you’ll need to make slight adjustments, maybe add or subtract 1/16” if need be. Remember that each adjustment changes the length of the other sides.
Using the same cutting technique as described above (e.g., place the scoring wheel of your glass cutter on the line, then bring the ruler to your glass cutter, secure the ruler firmly with one hand, and score firmly – one time – with the other hand), cut the diagonal sides of your octagon.
Snap off the scored corners.
You may or may not run into a case where a snapped edge doesn’t break perfectly perpendicular to the mirror’s surface. I was concerned about this, but as it turns out, it’s hardly noticeable after you sand and paint.
Use glass cleaner to wash your mirror. Let it dry thoroughly.
It’s time to start marking the lines that will create the jewel effect on your gem mirror. First, mark the very center of each of the eight sides. Tip: Rather than measuring half the side length (e.g., 5”) from one corner, which can create an off-center mark if your sides are not all exactly perfectly the same, do this instead: center your ruler between two numbers (in this case, I used the 5” and 15” marks) and mark the center in this way.
After the centers are marked, connect every other center point with a straight line. This will actually create two squares within your octagon (the A and B squares in the photo).
Draw a short line from each octagon corner to the intersection directly in “front” of it.
Your mirror lines should look like this – if it does, your gem mirror is off to a great start!
Now it’s time to “draw” two more squares in the center of everything. Connect every other intersection that is in “front” of each octagon outer corner (these are the intersections you just drew your short lines to). This will form the red and blue squares as seen in the photo.
Using a drop of glass cleaner on a cloth, wipe away the line that is parallel to and directly in “front” of each of the octagon’s sides.
(For your reference, or if your brain works this way, you’re wiping away the center part of each side of your two original squares that you drew at the beginning.)
Congratulations! You’re done with all the lines. It’s not time to prep your mirror for painting. Cover it carefully with clear contact paper.
Tip: Use as few pieces of contact paper as possible – one solid sheet of contact paper is ideal. The seams between pieces of contact paper aren’t as crisp for painting as the single-layer ones. Any paint leaks can be taken care of, but it’s just easier with a solid contact paper layer to begin with.
Choose the width of gem lines that you like best. This example shows about 1/4″ lines, which means I cut 1/8” off either side of the drawn lines (shown with the red marks in the photo). Use a razor blade and follow the ruler’s edge precisely to cut around each line. Tip: Use a sharp, or new, razor blade. You don’t have to press hard at all if your blade is sharp – you’re not trying to score the mirror anymore!
Use the razor blade’s point to lift the end of your strip.
Peel away your strip of contact paper. Continue for all gem lines. I found this step highly therapeutic.
Whatever the width of your line strip cuts, use this same width to cut the contact paper along all eight sides of your octagon. So, even though I was cutting 1/8” on either side of my lines, I cut a full 1/4″ from the octagon sides. Peel these edge strips away.
This next step is optional. Because you will be painting over your exposed lines, you would be fine leaving them. However, I like to start with a clean surface whenever possible, so I wiped them clean. Again, put a drop of glass cleaner on your glass cleaning cloth, and wipe them, from the center of the line toward the corners. Tip: Don’t wipe from one corner to another, as your first corner might pull up. Make two passes, both starting in the center and wiping outward.
One benefit of doing this step is that it also clears away any tiny triangle pieces of contact paper that you may have missed in your original removal of the line strips. If you didn’t miss any bits, congratulations. You’re a perfect DIY specimen.
With all line and edge strips removed and the lines (and triangular bits) all wiped away, lightly sand the edges of your mirror to remove any and all sharp spots. Use a fine grit sandpaper (I used 220).
Carefully wipe your mirror clean from your sanding – take care not to inadvertently peel up any contact paper corners. Place your mirror on a drop cloth and spray paint it. I used Krylon’s foil metallic spray paint in copper.
Make light passes with the spray paint; two light coats will probably be fine. Don’t forget to spray the sides of your mirror as well. Let the spray paint dry thoroughly.
Use the tip of your razor blade and peel up the corners of your contact paper. (Hey, if you like these concrete countertops, check out how to DIY them yourself here.)
Peel the contact paper.
It’s exciting, isn’t it? Looking good!
Remember when I mentioned that wherever you have seams in your contact paper, the paint will leak a bit? That happened here. Notice all the red arrows. It’s not a big deal, though.
Simply use the tip of your razor blade to scrape the smudges away. You don’t have to press hard – a light scraping will suffice.
And with that, you’re done! It’s beautiful.
You could use heavy duty 3M hanging strips to hang this mirror anywhere, or you can prop it on a shelf or mantel for all to enjoy.
Such a chic, unique piece. And you made it yourself! You should feel proud.
We love how the gem mirror looks complex, sophisticated, yet subtle.
A little modern geometric vibe amidst traditional décor.
It even stands out in the semi-dark.
Mirrors are a great tool for increasing light in any space.
What a gorgeous “tool.”
We hope you enjoy creating your gem mirror as much as you love displaying it!