To make a plain glass jar look like mercury glass, spray the inside with water, spray mirror paint over the water, and let dry. The water droplets keep the paint from adhering completely to the glass, giving it a mottled appearance.
Mercury glass is clear glass that is double-walled. There is a silver coating between the glass walls that is inserted through a small hole then sealed. There is an easier way to give glass objects the appearance of mercury glass.
Gather the supplies
The only supplies needed for this project are a spray bottle with water, silver mirror spray and glass objects such as votives or a hurricane glass.
Coat with water
Use the spray bottle to coat the inside of the votive or hurricane with water. Be sure the nozzle is set to "spray" rather than "stream," as it is important to have just a light mist.
Coat with paint
Immediately after spraying the object with water, spray the surface with the mirror paint. Spray it on top of the water, before it dries, as the drops of water help create the mercury glass look.
Let the object dry and, if desired, repeat the process until the desired shade and look is acquired.