Tempera - course pigments bound with egg yolk and prone to flaking; fryable media should not be encapsulated or covered with acrylic sheeting due to it's static charge; protein rich binder attracts mold.
Gouache - applied thicker than water colors due to large pigment size; pigments are ground with water and mixed with gum; prone to cracking; binder attracts mold (black spots); lead carbonate in gouache eventually turns black.
Watercolors - thin wash of pigment on paper; some pigments unstable and will fade in light exposure.
Metal point drawings - silver, lead, etc. made into a rod and then applied to a polished gesso board; over time the metal will tarnish and become darker; predecessor to graphite drawings.
Graphite pencils (1795) - Invented by Nicholas Jacques Conte; made of powdered graphite and clay; as smooth and hard as pure graphite; a harder or softer writing core can be produced by varying the proportions of clay and graphite; stabile in light; does not harm substrate.
Charcoal - impure form of elemental carbon made by burning selected woods, willow, plum, birch, and vines, in anaerobic conditions; fryable media that will come off on fingers or through static electricity; careful handling; no encapsulation or acrylic sheeting; stable in light.
Chalk (15th century) - after the 18th century fabricated chalks are made from dirt, calcium carbonate, and colored pigments; fryable media vulnerable to smudging and static electricity; careful handling; no encapsulation or acrylic sheeting; natural chalk stable in light; manufactured chalk unstable in light.
Pastels - soft, intensity determined by ratio of binder to pigment; rough tooth papers used to hold the pastel; highly sensitive to abrasion; fryable media; no encapsulation or acrylic sheeting.
Ink is any liquid or viscous substance used for writing, printing or drawing. Ink composition and consistency may vary. However, all ink types are made up of two components: a colorant and vehicle. A colorant is also known as a pigment or dye, while a vehicle is defined as a liquid (i.e., water, alcohol or another solvent) into which the colorant is dispersed.
Iron gall (17th century) - brown/black color; pigments are highly acidic and will eat through paper where ink is present.
Black ink (19th century) - carbon black ink made in Europe in the 11th century, also known as India or Chinese ink; comes from finely ground soot "lampblack" and various resins; carbon based ink is very stable and will not fade.
Bistre (14th - 19th century) - brown lamp black or soot brown; made from tarry soot collected in wood stove chimneys; the color of this ink can be altered by the concentration and source of soot; colors range from dark blackish brown to brownish-saffron yellow; handmade by artist; bound and thickened with gums allowing the ink to lay on the surface instead of soaking into the paper.
Blue/black ink (19th century) - use of unstable dyes such as Prussian blue mixed with ivory black, varnish and eggs; light sensitive, fades to bluish grey or pale brown.
Sepia (19th century) - black/grey, hint of brown; made from the ink sacks of cuttlefish; used to write and produce mono-chromatic drawings; semi-stable but should be protected from ultra-violet exposure.