Golden ochre
Golden ochre,less oftenGold Ochre(French:Ocre d’or,German:Gold OckerотAncient Greek:ὠχρόςyellow-pale,orangeorfrench ochre(obsolete)) — one of the most famous and brightly colored varieties ofochre— is a natural or (rarely) artificialpigment.In terms of mineral composition, golden ochre isclaywith an admixture ofaluminosilicatesand a high content of the yellow dye itself,iron hydroxide,most often in the form ofbrown iron oreorlimonite.The exact composition of ochre and its impurities vary greatly depending on the place of origin.
Golden ochre is one of the oldest paints, known as a painting material since the times of cavepaintings.In wall painting it is one of the mainyellowpigments. Golden ochre has good density, the same covering power, high light fastness, pure color and soft structure. To this day it is used in all painting techniques without exception.
Description and properties
[edit]The golden ochre pigment is a natural mixture that consists primarily of crystalline iron oxide hydrate with someclay.The closest to golden ochre among related minerals islight ochre,which has a less warm and rich color. If in light ochre the content of the main dye,iron oxide hydrate,is quite low and ranges from 12 to 25%, then in golden ochre its amount can reach 70-75%. As a result, light ochre has a yellow color of a cooler tone and weaker color saturation and is considered a paint that is not bright and not intense. Golden ochre differs from it in its earthy tint and warmer tone.[1]
Yellow ochres are more common in nature than others due to the abundance of their constituent minerals. When heated, orange and yellow ochre release water and gradually darken, acquiring an increasingly reddish tint. This occurs due to the transformation of iron hydroxide into a dark red anhydrous oxide (iron ochre). With controlled calcination of yellow ochre, almost the entire range of shades can be obtained from yellow and orange to red or brown.[2]: 173
Among other varieties of ochres, it was golden ochre that was valued above others; it was classified as the highest category of pigments in this category. In the 18th-19th centuries, golden ochre was supplied to the rest ofEuropeandRussiafrom the province ofRousillon,as a result of which the second name of this paint for a long time wasFrench ochre.[3]: 426 Of the total number of ochres, it is the golden ochre pigment that is closer in purity, brightness and shade all toAttic ochre,the most highly valued yellow paint ofAncient GreeceandRome.
Until the mid-20th century, picturesque yellow ochres were traditionally divided into fawn, yellow,saffron yellow,golden and orange. In the modern artist's palette,four typesof nominal yellow ochre are most often encountered: light, medium, golden and dark. Natural and Italiansiennacan also be considered among the same paints. In terms of composition, golden ochre should include at least 53%Fe2O3,5%Al2O3and 34%SiO2with the complete absence of impurities such asCaO,MgO,MnO2and insolublesulfates.For comparison: of all yellow ochres, only dark ochre contains moreiron oxide(more than 60%).[2]: 173
History and use
[edit]
Golden ochre is best known as a mineral pigment common in nature, primarily for artistic paints. It has been found since ancient times inrock paintings,frescoesofAncient Egypt,GreeceandRome.Thispigmentwas also constantly used when painting temples and iniconpainting. When analyzing the colorful composition of the icons ofTheophan the Greek,despite all the restraint of his color scheme, golden ochre was clearly established.[4]
Golden ochre is also used in the production and restoration of expensive types offurniture.For example, when oilgildingonlevkas(gesso), several layers of golden ochre are first applied in oil, and then, after drying and grinding, they are coated with oil gulfarbene varnish. As a result, the surface for gilding is perfectly matte and retains the color of thefoil.Gilding on carvings looks especially impressive if shiny polished areas alternate with matte ones.[5]
As an artist's paint, golden ochre has traditionally been a staple in artistspalettes,primarily inoil painting,but also intempera(includingwatercolor) and more recently,acrylic.It is stable both in pure form and in mixtures. However, when writing with tempera or watercolor, it is necessary to take into account one feature of ochre, dictated by its mineral nature: with a large amount of water-soluble film former, there is a risk of pigment precipitation (bothaluminaandiron hydroxide), so it is recommended to use ochre in the form of a thick paste.[2]: 173
The muted, slightly "earthy" shade of golden ochre makes it possible to achieve a soft and warm color palette of the painting and, in mixtures with brighter paints, to slightly "reduce" their color activity. There is one more feature. It is generally recommended to avoid very large, raised strokes with pure ochre, since due to the slow and incomplete drying of the layers to the full depth, uneven color and irregular matte surface may appear.[1]The disadvantages of golden ochre include its vulnerability in case of close friction withmetal(for example, in the case of rubbing with apalette knife). After some time, such contact can cause the ochre to turn green.[6]
Oftenlight ochreor golden ochre is used to give the painting the impression of external monochrome or unity of color, and also to ensure that the light in the painting does not look colder than the shadow. In this case, ochre performs not only the function of enhancing the feeling of unity of the picture, but also an additional "warming" color.[7]: 236
Golden ochre has been known and widely used as a stable, reliable and inexpensive pigment for any finishing, household and decorative purposes, suitable for painting both interior and exterior work. It does not fade and can withstand almost any weather conditions. A description of a similar use of golden ochre can be found in one of the stories of the Russian writerSergeev-Tsensky:«...Thehiveswere squat, wide, on four oak logs each, with pitched roofs, covered here with iron, here with plywood, but uniformly painted with golden ochre, cheerful in appearance».[8]: 261
Along with other types of ochre, golden ochre is traditionally widely used in tinting and painting ceramics.
See also
[edit]- Ochre
- Attic ochre
- Ochre (disambiguation)
- Iron ochre
- Clay
- List of inorganic pigments
- List of colors
- Yellow
References
[edit]- ^abErmakov G. I.Plein air. Textbook for students of higher educational institutions. — Moscow: MPGU: Prometheus, 2013. — 160 p.
- ^abcA. M. Nikitin.Artistic paints and materials. Directory. — Moscow: Infra-Engineering, 2021.
- ^Journal of generally useful informationor Library of agriculture, industry, agriculture, sciences, arts, crafts and all kinds of useful knowledge. Editor E. P. Pertsov. Volume I. — St. Petersburg: in the printing house of Military Educational Institutions, 1852.
- ^Svetlana EremeevaLectures on art history. — Moscow: Publishing House Home Computer, 1999.
- ^Tatyana Matveeva.Restoration of joinery and furniture products. — Moscow: Higher School, 1988.
- ^Prokofiev N. I.Painting. Painting technique and technology of painting materials. — Moscow: VLADOS Publishing Center, 2010. — 158 p.
- ^Anastasia Shimshilashvili.Oil painting from A to Z. Oil portrait. — Moscow: Apple Books, 2022. — 320 p.
- ^Sergeev-Tsensky S. N.Collected works in 12 volumes, Volume 3. — Moscow, Pravda, 1967.