Wikipedia
Blockwash
Blockwash is an art technique that made its debut on January 26, 2008, at the 23rd Annual Juried All Media Art Exhibition in Lancaster, California. It was created by the artist Bryan D. Pacana. The blockwash technique can be used on various surfaces such as stretched primed canvas or watercolor paper. It involves using pure pigment which is to be used as the base, varnish to "block" and protect the portions of the painting, and water to douse or "wash" the painting and remove the unprotected layers of pigment. Hence the term block+wash. The result is a painting that was described by a judge as "an excellent blend" between the white painting surface and the protected layers of pigment.