Creating a Sandstone Mantle

One of the most impressive looks for the fireplace available today is the 'cast stone' mantle and hearth.  As the name would imply, this mantle and hearth system is usually cast in cement or plaster and comes in one color.  White.  While the look of the mantle is one of stone blocks complete with mortar lines and even divot imperfections in the stone, it looks like a white plaster cast.  So the buyer is expected to somehow paint it to make it look like real stone.

Often a good faux finisher can be hired to make this mantle system look as it was intended.  You might choose to have it look like marble, or granite.  However the most often desired look is sandstone.  This is also the easiest technique to reproduce.  It requires only a few tools and a minimum of paint material.

First you will need a good 2 1/2 inch paint brush that is suitable for use in water based paint.  Then you will need a good lint free cloth like an old washed white cotton tee shirt.  You will also need two clean 1 gallon size pails to use as you paint the mantle.

Now you should decide what color you want the mantle to be.  Obviously the sandstone look will be in earth tones, tan, beige, taupe.  I've never seen blue or green sandstone.  I guess there is a first time for everything.  But if you want it to look authentic choose three colors in the tan/taupe family.  One light, one a little darker, and one near brown.  You need only to buy these colors in quarts and the amount of paint you use will be minimal.  Also if you have a little white left in a can around the house you will need this too.  If not, pick up a quart of white.  You will also need a quart of latex glaze in which to mix some of the paint.  So where are we so far?

Tools: 

2 1/2 inch latex brush
clean white cotton cloth
old tooth brush
2 one gallon pails

Materials:

1 quart  light tan paint
1 quart darker tan paint
1 quart brown paint
1 quart white paint
1 quart latex glaze

All of this can purchased for less than $100 at your local paint store or Home Depot.

Instructions:

1. First quickly do a base coat with the light tan color.  Paint the mantle system completely so that there will be no voids or 'holidays' in the next coat.  Allow this coat to dry completely.  It will probably take 2 to 4 hours before you would be comfortable for the next step.

2. Next pour some of the light tan into a paint pail and some of the darker tan into the other pail.  Then add just a little water.  About 1/4 cup to half a quart should be about right.  What I want you to do now will require a little concentration.  Take your brush and dip it into the light color and brush out a small area of one of the stones.  Then without cleaning it dip the brush into the darker color and brush out the next little area beside the lighter color all the while brushing the paint in a criss cross manner letting the darker color blend back into the lighter color around the edges.  Continue to do this going back and forth from one color to the other with the same brush.  As you cover the entire mantle system in this way you will see develop a color blended light and dark, high and low that is typical of the color variation found naturally in such stone.

3. Now allow this color blended coat to dry completely.  Again allow at least 2 hours, and if conditions warrant as much as 4 hours.

4. The next process is simple.  Take some of the remaining darker paint and mix it in your glaze.  Use about a 4 part glaze to one part paint formula.  I would suggest one cup of glaze to 1/4 cup paint.  Then add about 1/8 cup of water and mix this well.  Paint this formula on just the grout lines and the divot marks in the stones.  Wait just a minute or so and wipe off the excess with your clean cloth slightly dampened.  This is intended to leave glaze mixture only in the depressions of the grout lines which will darken them and the divot holes and will make the stone look more natural and real.

5. What is the tooth brush for?  This is fun.  Mix a little of the brown paint with water so that it is thin and a little watery. Do this with the white paint as well.  Then dip the tooth brush bristles in the brown paint and stand back a little and flick or spatter some of the brown on the surface of the stone.  Do this by running your thumb or finger along the bristles so that they will splatter a little of the paint on the surface.  You must have done something like this to your siblings as you were brushing your teeth while growing up.  If not you missed out.  Any way be careful not to make this spattering so heavy that it runs.  It needs to be very light and airy.  Do the same thing with the white mixture.

6. Let it all dry to touch and if you like you may add one more coat of low luster clear water based urethane.  This is optional and only for protection.

All of this you can do yourself for about $100 in material and tool cost.  If you hire a faux finish artist you may expect to pay somewhere in the neighborhood of $800 to $1200.  Nice neighborhood. 

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