Gesso grounds

F. Ronca, Protein Determination in Polychromed Stone Sculptures, Stuccoes and Gesso Grounds, Studies in Conservation, 39, 107 120 (1994). 

Either of these gesso grounds will provide a brilliant white painting surface. Unlike a fresco painting, in a gesso painting the artwork is painted on a dry surface and does not soak into the surface. 

Gesso is also used when preparing a canvas for oil or acrylic painting. Canvas stretched on a frame is the support. The gesso ground is applied with a brush to the support, a procedure called priming. The gesso acts to seal the canvas fabric so that the paint applied will not soak into the canvas. 

Compare the whiting compounds, CaC03 and Ca(OH)2, for brightness, texture, and consistency. Which compound would be a better whitener for a gesso ground Why ... 

Students will compare and contrast the properties of various types of gesso grounds. 

Students will debate the pros and cons of using a gesso ground for a painting. Materials... 

C. Have students create a gesso ground by applying the gesso to a masonite board ... 

Compare the gesso grounds prepared with regard to color and texture. 

In a class discussion, have students decide which gesso ground is the best ground for a two-dimensional work of art. 

In Activity 3.3 you will experiment with nonobjective art using the gesso grounds prepared in Activity 3.2 and egg tempera paint prepared in Activity 2.5. Egg tempera was used by many artists in Europe during the fourteenth and fifteenth centuries. Today, it is still used by some artists, notably Andrew Wyeth. In this technique, egg yolk is mixed with distilled water to form a binder, and a pigment is added to make egg tempera paint, which is applied to a gesso ground. 

Students will apply paint to a prepared gesso ground. 

Egg yolks, pigments (see below), powdered or liquid tempera (poster paint) in assorted colors, and distilled water, or egg tempera paint prepared in Activities 2.3-2.5 gesso grounds prepared in Activity 3.2 narrow-width paintbrushes with soft bristles paper towels mixing trays water containers pencils. 

Paint on the gesso ground to create a feeling of movement—across, up, down, around, in, out, or any combination of these—using shapes and lines. 

A whiting compound is an insoluble, very white substance that provides a smooth, solid coating needed in a gesso ground. 

Activity 3.3 Nonobjective Art Egg Tempera Paint on a Gesso Ground.. 131 Support for the Artist Paper.132... 

In a discussion of mediaeval gesso grounds, Federspiel (1995) has noted that anhydrite burnt at temperatures in excess of 900°C will form so-called Estrich gypsum, a mixture of anhydrite and calcium oxide (qq.v). This reacts slowly with water and becomes extremely hard. Federspiel also suggests that the inefficient furnaces of the past could well in part produce such materials. 

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