Here is a lesson in Italian for you:  Buon Fresco, Fresco Secco, arriccio and intonaca.  Oh, and faux fresco!

I've painting a few murals using the fresco secco technique of painting; that is painting acrylic paint into a dry plaster wall: the final effect is a wall mural that looks a thousand years old.

I had the opportunity to paint a mural in the buon fresco technique.  That means "true-fresh"--in this context referring to the dampness of the freshly applied  lime plaster on which the paints are applied.   First a base coat of coarse plaster called the arriccio is applied to a wall or ceiling.  The late Medieval and early Renaissance masters of fresco (Giotto, Masaccio and others) roughed out their mural schemes in charcoal and red pigment onto this surface.  Then the second layer of finer, smoother plaster mixed with marble dust is trowelled on, called the intonaco.  Onto this surface, the mural or decoration is painted.  Check out a sample.

The actual painting part of buon fresco is truly enjoyable!  After the intonaco sets up a little, the paint flows off the brush into an absorbant wall that "drinks" the paint.  The final effect is spectacular.  Not only is the wall changed from drywall into stone, with the paint becoming part of the stone, also it looks as ancient as the medium itself.   To modern eyes, the revelation of a contemporary vision of the fresco technique in its simplest form is the astonishing beauty if the color--so clear and pure as to be almost incandescent, but relieved from inhuman perfection by the minute variations in the intonaco surface.  Check out How to Paint a Fresco.

I've also invented a term of my own:  faux fresco.  I have always experimented using unusual mediums to achieve desired effects. Faux fresco is water media painting into drywall joint compound that has the look and feel of buon fresco but with a lot less manpower. First the walls are trowelled with joint compound rougthly to make the surface look old, then after dry, washes of color are painted into the "thirsty" wall. Once the mural is done, the wall may be further aged by sanding back the surface a little or a lot depending on how old the mural needs to look. Faux fresco is a great alternative to real fresco because it's less manpower, and therefore less cost.  Check out a sample.