I absolutely love the look of mercury glass, but it's so expensive! So, I decided to try and create something myself using a plain glass head and Krylon "Looking Glass" spray paint. It was so easy and worked really well.
What you'll need. Any glass object, Krylon "Looking Glass" spray paint, and a spray bottle capable of spraying a fine mist of water. Fill the spray bottle with water and a couple drops of vinegar.
Now you are ready to turn anything glass into mercury glass...
Spray the back side of your object with water until it starts to form droplets. For this head, I sprayed the inside. Then spray a light mist of the mirrored paint. Let it dry and keep alternating. Spray again with water, spray with paint. Let it dry. Drying only takes a few minutes and it doesn't have to be completely dry to keep going. The water will repel the paint from sticking to the glass and after a few times you will start to see bubbling and streaks in your glass. This is the mercury effect you are going for.
Just keep at it until you start to see the mirror shining. You can then blot your item carefully with paper towels. I'm really happy with how the final item looks. It would look right at home in Anthropologie (my favorite shop). If you do it on a vase, you will have to put another smaller container inside to hold water since this surface is delicate and will not be good for cut flowers. Give it a try, it's super easy and makes a really impressive piece.