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Ochre, Luberon Red [100 g jar] (3.5 oz.)
Item No: 450:520100
Category: 29
Price:
$4.30
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Quantity:
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Description:
100 g jar (3.5 oz.)
Our French ochre is from the last remaining European company operating the ochre deposits in the French quarries of Gargas and Rustrel nestled in a 12 mile long enclave in the heart of the Luberon Mastiff, the ochre country. Ochre is a symphony of colors ranging from pale yellow through the orange range to an intense red. It has two major characteristics: it never fades in daylight and the color is highly concentrated.
| Common Names: |
English: red ochre
French: ocre rouge
German: Ocker rot
Italian: ocra rosso
Russian: ???? ???????
Spanish: ocre rojo |
Origin and History
Known since the antiquity, ochre (okhra in Greek) occurs naturally as yellow ochre (limonite) or as red ochre (hematite). Ochre has been used as a pigment since prehistoric times and is perhaps the most widely used pigment for artists paints.
Source
Ochre is a natural earth containing clay tinted by hydrated iron oxide and is composed of a naturally calcined form of limonite and goethite, and traces of gypsum or manganese carbonate. Limonite is a general term used to describe all forms of hydrated iron oxide minerals (FeO(OH)) that occur as natural clay or earth. Limonite includes the minerals goethite, akaganeite and lepidocrocite. To be considered an ochre, the content of iron oxide must not be less than 12%. Depending upon the content of hydrated iron oxide, the color of ochre varies from light yellow to orange-red. Most yellow ochre are normally not calcined as heat does relatively little to alter their color. Like red iron oxides (hematite), they are found around the world and have been used as pigments since prehistory. French ochre, historically one of the best grades of limonite, contains about 20% iron oxide and is high in silica.
Ochre grades into sienna, a yellow-brown pigment containing a higher percentage of iron ore than ochre as well as some manganese dioxide. Sienna grades into umber, which is darker brown and contains a higher percentage of manganese dioxide. Burnt sienna is brown or bright red, burnt umber is a darker brown than umber.
Ochre is not naturally usable as a pigment and therefore needs to undergo several important processes, such as:
- Extract ore from the quarries.
- Separate ochre from sand using water and centripetal force.
- Calcine (roast) raw yellow ochre to obtain red ochre by heating it for 15 minutes at a temperature between 932°F and 1112°F.
- Blend different ochre extracted from diverse veins to obtain the selected colors.
- Grind to 50 microns and pack.
Permanence and Compatibility
Ochre is among the most permanent colors among the artist's palette. It is compatible with all other pigments, and can be used with good results in all mediums.
Oil Absorption and Grinding
Ochre absorbs a moderately high amount of oil. The oil absorption ratio is 6–21 parts by weight of pigment to 100 parts by weight of linseed oil. If the measurement were grams, umber would require 100 grams (by weight) of linseed oil to grind 6 to 21 grams (by weight) of pigment to form a stiff paste. It slows the drying of oil paint, but forms an excellent film.
Toxicity
Ochre is not considered toxic, but care should be used in handling the dry powder pigment to avoid inhaling the dust.
Pigment: French Red Ochre (Luberon)
| Color: |
Red |
| Colour Index: |
Pigment Red 102 (77491) |
| Chemical Name: |
Iron Oxide |
| Chemical Formula: |
Fe2O3 |
| ASTM Lightfastness Rating |
| Acrylic: |
I |
| Oil: |
I |
| Watercolor: |
I |
| Properties |
| Density: |
5.27 |
| Hardness: |
5.0–6.0 |
| Refractive Index: |
2.78–3.01 |
 Read cautions about handling pigments
Availability: Usually ships within 24 hours.
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