How to Burnish Venetian Plaster

Prepare to begin burnishing when the plaster is tacky-wet, before the Venetian plaster dries. This helps ensure that you don’t over-work the plaster and leave unwanted marks or ridges as it starts setting. Work in small areas and have someone help you if possible.

Using a clean steel spatula, go over the area holding the steel spatula at a five-degree angle. Rub quickly in a circular motion while applying pressure to the spatula. You'll begin to notice a gloss beginning to appear over the surface as you burnish--the degree of glossiness will vary in different areas of the plaster--and the color will begin to deepen in some areas. The more you burnish, the more the surface will glow with the sheen or polish you are creating with the steel spatula. Burnish until you've reached the level of sheen desired. You can also use a super-fine (#0000) steel wool to burnish. Steel wool tends to blend the color variations more and bring out more of a sheen than a steel spatula.

Apply a thin layer patch of Venetian plaster over an area if you accidentally nick or scratch the plaster. Repeat steps 1 through 3.

Clean the surface with a soft, clean cloth to remove any residue from burnishing after the plaster is dry, and before sealing.

Apply a sealer, such as liquid soap (which may deepen the color), beeswax (which brings out the plaster's natural luster) or a synthetic sealer specifically designed for stucco or natural stone (make sure you use a non-enhancing synthetic sealer so it won't change the color). Sealing the plaster makes the plastered surface more durable, easier to clean, and helps it maintain it's color and sheen. When sealing with liquid soap, mix a liquid soap (don't use solid soap) or a clear shampoo mixed with water (1-to-1 ratio). Wipe the liquid soap/water mixture on with a clean cloth after the plaster has dried completely. If you opt for beeswax, apply after the plaster is dry in thin coats with a soft cloth and buff after each coat. Synthetic sealers should be used in high-traffic or high-moisture spaces. Synthetic sealers can be brushed, rolled, wiped or sprayed on (follow instructions on the label). A clear sealer will deepen the color of your Venetian plaster and give it a satin sheen. If you're looking for more of a glossy sheen, burnish the surface to a high-gloss finish, then seal.