Chlorite

Chlorite is a natural mineral pigment powder ground from chlorite, a soft, mica-like sheet-silicate mineral, in a muted gray-green. It belongs to the green earth family (PG23) and is lightfast and lime-proof: a quiet, natural green for landscapes, shadows and underpainting in oil, egg tempera, watercolor and fresco.

Key facts

• Color: muted gray-green
• Pigment type: Natural mineral pigment (chlorite, a green-earth-type pigment)
• Colour Index: PG23 (C.I. 77009)
• Composition: chlorite-group sheet silicate of magnesium, iron and aluminum, (Mg,Fe)₃(Si,Al)₄O₁₀(OH)₂·(Mg,Fe)₃(OH)₆
• Opacity: semi-transparent (sold as a glazing pigment)
• Lightfastness: 8 of 8 on the Blue Wool Scale (supplier data)
• Chemical resistance: alkali 5/5, lime 5/5 (supplier data, 5 = best)
• Suitable for: oil, acrylic, egg tempera, watercolor, gouache, fresco (lime), lime and cement plaster
• Packaging: 50 g jar · 1 kg bag

How to use

Grind the powder into egg yolk for tempera, gum arabic for watercolor and gouache, acrylic medium or linseed oil with a palette knife or muller. Chlorite is soft (Mohs 2–2.5) and disperses easily; grind gently, as over-grinding makes natural mineral pigments paler. Thin layers glaze; apply several coats for fuller coverage. It is lime-proof, so it can be used in fresco and to tint lime or cement plaster. Mix it with ochres and umbers for natural landscape greens.

About chlorite

The chlorite group takes its name from the Greek chloros, "green". These minerals form mainly in low-grade metamorphic rocks, where chlorite is the key mineral of greenschist, and as an alteration product in igneous rocks. Alongside celadonite and glauconite, chlorite is one of the minerals that have been used as green earth pigment.

Safety

Natural earths and ground minerals can contain crystalline silica: avoid breathing the dust. Handle dry pigment with care: avoid breathing the dust and contact with eyes. Wear a dust mask (FFP2/N95) and gloves when working with the powder, work in a well-ventilated area and wipe up spills with a damp cloth. Do not eat, drink or smoke while working; wash your hands afterwards. Keep away from children and pets. For artistic and technical use only — not for cosmetics, food or tattoos.

FAQ

What is the difference between chlorite and glauconite?

Both are green sheet silicates used as green earth. Glauconite is an iron-potassium mica formed in marine sediments; chlorite is a magnesium-iron silicate formed mainly in metamorphic rocks. Our Chlorite is grayer than our glauconite greens.

Which chlorite shades do you sell?

Chlorite (muted gray-green), Chlorite green dark (very dark gray-green) and Chlorite tobacco (brownish olive green). All three are natural chlorite with the same lightfastness and lime resistance (supplier data).