Another tempera grassa recipe

Those who’ve been read­ing here for awhile or have delved into the archives know that I’ve some­times exper­i­mented with a tra­di­tional paint­ing medium called tem­pera grassa. TG was most com­monly used in the 15^th and 16^th cen­turies; it rep­re­sents a tran­si­tional medium between egg tem­pera and true oil paint­ing. TG con­sists of pig­ment mixed with an emul­sion of egg and oil. Since the 16^th cen­tury, TG has been fairly obscure—the best recent exam­ple would be the 20^th cen­tury Ital­ian mas­ter, Pietro Annigoni.

In the 19^th cen­tury (espe­cially in Ger­many), paint­ing recipes were devel­oped that involved var­i­ous com­bi­na­tions of tem­pera ingre­di­ents, often includ­ing some com­bi­na­tion of egg white, whole egg, lin­seed oil, stand oil, dammar var­nish, stand oil, and tur­pen­tine. You can find many such recipes on the inter­net with a few sim­ple Google searches. I’ve usu­ally avoided these rel­a­tively com­plex recipes in favor of sim­ple emul­sions of egg yolk (the tra­di­tional binder for egg tem­pera) and lin­seed or wal­nut oil, mixed with pigment/water paste.

Recently, I ran across a web reprint of Egg Tem­pera Paint­ing, Tem­pera Under­paint­ing, Oil Emul­sion Paint­ing: A Man­ual of Tech­nique, by Vaclav Vit­la­cyl and Rupert David­son Turn­bull. Pub­lished in 1935, it is a com­pendium of var­i­ous tem­pera tech­niques. One that caught my eye is a recipe they call “putrido.” Putrido is one name for tem­pera grassa (because it starts to smell bad after a few days). They say that this is based on a recipe from an old man­u­script found in Venice. For all I know it’s what was used in the Renaissance.

Take what­ever quan­tity of dry color you wish to pre­pare. Divide it into two equal parts. Rub up one part with yolk of egg only into a fairly stiff paste. Rub up the other part with sun-bleached lin­seed oil, to about the con­sis­tency of ordi­nary tube colours. (To save time or trou­ble, it is pos­si­ble to use ordi­nary tube oil colours, but to be sure of your ingre­di­ents, it is always advis­able to grind your own colour in oil.) The part that is rubbed up with oil may be slightly larger in quan­tity than the part rubbed with yolk of egg. Then take the two parts so pre­pared and grind them together, prefer­ably on the mar­ble slab. It will be found that when these two parts are put together, the resul­tant mix­ture will stiffen at once into a very stiff paste, too stiff to be eas­ily rubbed. This may be soft­ened down by the addi­tion of either water, emul­sion, or lin­seed oil. If you wish to use the Putrido in its leaner form, add either water or the emul­sion (Medium Fat Emul­sion), but if you wish to paint with it as an oil paint using oil as the medium, then thin it down with oil. In either case, add the water, the emul­sion, or the oil very slowly, only a few drops at a time, until the paste becomes a smooth cream eas­ily han­dled on the mar­ble slab.

I find this to be pretty inter­est­ing. It is a recipe that is sim­i­lar to what I’ve done before, is sim­ple to make, doesn’t involve sol­vents, and uses egg yolk (rather than the white or the whole egg), with which I am more famil­iar. They sug­gest that adding a small amount of oil of clove will pre­serve the paint mix­ture and allow it to be kept for some time (although not indef­i­nitely). I expect that stor­ing them in a refrig­er­a­tor, espe­cially in warm weather, would be a good idea. The oil of clove would also act as a retarder for the oil com­po­nent of the paint, caus­ing to dry more slowly. That could be a good or a bad thing, but I expect one would have to wait between lay­ers for the paint to dry. You could try to bal­ance the retard­ing effect of the clove oil by adding a small amount of lead napthen­ate, but that makes for a more com­plex reac­tion than I am really com­fort­able with.

I’ll have to try this recipe soon. I have a large paint­ing that I started in tem­pera and then stopped work on. It might make an excel­lent under­paint­ing for this TG recipe.