Manufacturing Process
1. Extracting the ore
2. Cleaning the ore prior to separation
3. Separating sand from ochre using centripetal force
Les Ocres de France is the only remaining European company operating the ocher deposits in the French quarries of Gargas and Rustrel, nested in a 12 miles long enclave, in the heart of the Luberon Mountains, the ocher country. The Provencal Ocher Massif has been registered by the French government in the Protected and Classified Natural Sites.
Ocher is a clay (Kaolinite, Aluminum Silicate) loaded with iron oxide (Goethite) where remains sandy residue too thin to be separated (Quartz), so ocher is a colored clay, but before been a color it's a material and a symphony of colors ranging from pale yellow through the orange range to an intense red.
The Process
Ocher is not naturally available and needs to undergo several important processes:
- Ore extraction in the quarries.
- Separation of ocher and sand using water and centripetal action for the cleaning procedure.
- Drying in open air from spring to summer before been stored.
- Calcinations of the raw yellow ocher to obtain red ocher by heating it for 15 minutes at a temperature between 932 - 1112ºF
The Environment
Ocher extraction at the Luberon quarries is a well-controlled mining process, paying strict attention to our environment. Air pollution is prevented by the use of dust removal devices installed in the factory's chimneys to clean the smoke before it is released into the air. A high volume of water is necessary to clean the ocher. Running in closed circuits allows for cleaning and recycling of this water. The separated sand, when not sold for different purposes, is returned to its original site. Extraction is done by machine, employing the technique of terracing to maintain structural integrity. Mined sites are then rebuilt with their original top layer of soil.
4. Ocher in water flows to a
decantation pond
5. Decantation process in open
air ponds
6. With water fully evaporated, the dried
Ocher is ready to be collected and
later ground and packaged at the factory