Slate is a hard and porous natural material easily painted on after priming. Used as a decorative addition to a flower garden, painted stepping stones through the backyard or even necklace charms, slate is found in all sizes. Paint and decorate the entire piece of slate, or just certain sections. In the final work of art, allow the beauty of the stone to come through.
Purchase slate at hardware or home improvement stores. Tile stores often have smaller broken pieces kept in a back room for artists creating mosaics. Also ask masons or home builders who work with stone if they have broken pieces available for purchase or for free.
Wash the slate with a sponge using mild soap and water. The scouring side of the sponge removes clumps of dirt that may be on the slate. Allow the slate to completely dry in sunlight before you prime.
Draw the design with a pencil or water-soluble marker directly onto the slate. This allows you to create a design so the rock can be seen in the areas you do not paint. If you plan to paint the entire piece of slate with no rock showing through on the final design, you do need to draw the design prior to priming the rock.
Use an appropriate-sized paintbrush to apply a layer of prime-coat paint, preparing a ground for acrylic paint so it won't peel or crack. Primer paint, also called Gesso, is white and easily found at art supply stores. You may need to add a tiny bit of water to the primer so it's the same consistency as pea soup.
Apply a second coat of primer paint to your slate. Allow each layer to dry completely before proceeding. You can lightly sand the dried primer paint if you desire a smoother surface. Sand in circles and brush off dust before adding fresh paint.
Use acrylic paint to create a design in the colours you choose. You may need to add water to the acrylic paint so it flows more evenly from your paintbrush. If you make a mistake, allow the paint to dry and then paint it again.
Place your completed slate painting in a dust-free room until dry.
Apply an acrylic glaze or sealant on your final painting. Brush the sealant liberally on top of your design to protect the painting. Purchase sealant and glaze at art stores or hobby shops. They dry clear and come in glossy or matt finishes.
Wash out your paintbrushes as soon as you finish painting your primer, colours or sealant. You cannot remove dried acrylic paint from paintbrushes once they harden.
All paintings when left in direct sunlight fade over time.