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Natural pigments

 

Cyprus was known in the antiquity for its natural pigments (Fig. 17) such as the umber (Fig. 18), the ochre (Fig. 19) and the terra verde.  The exploitation of these materials is still ongoing.

 

Umber is a dark/yellowish brown or almost black ferruginous (containing iron) sediment rich in manganese and has been used since ancient times as a pigment.  The deposits are generally earthy and friable.  The commercial deposits are widespread but generally occur as small lenticular bodies in depressions on top of the Upper Pillow Lava and at the base of the Perapedhi Formation.  Although the majority of the deposits are only 2 to 3 m in thickness, large deposits exceeding one million tonnes have historically been found.  Minor deposits also occur as inter-lava horizons within in the pillow lava sequence of the ophiolite.

 

Umber was initially thought to have been derived from weathering of iron-bearing minerals and manganese in the underlying pillow lavas.  However, all of the field evidence is consistent with an origin of umber as a chemical precipitate, which originated in the widespread activity of submarine thermal springs during the waning stages of Upper Pillow Lava volcanism.  Large volumes of metalliferous (containing metals) solutions were exhaled into oxidizing seawater, followed by umber precipitation.  Umber deposition has often been tectonically controlled and most deposits occur along fault zones.

 

The umber is excavated sporadically and transported to the factory for grinding and packing. Burning can also be undertaken to modify the colour and the burnt and unburnt mineral can be blended to achieve the required shade. It is primarily used as an industrial pigment and has excellent stability. It has also been used for centuries as an artist pigment and in ceramics and pottery, although these uses are subsidiary.

 

The ochre deposits are limited and directly associated with the sulphide deposits.  Ochre is mainly composed of iron oxides and hydroxides that give its characteristic yellowish colour.  Ochre forms during the submarine oxidation of massive sulphide ores.

 

The third natural pigment found in Cyprus is the so-called terra verde (green earth).  It has a characteristic green colour and is composed of the mineral celadonite.  It is a product of the alteration of the Lower Pillow Lavas which is found in irregular veins.

Cyprus was known in the antiquity for its natural pigments (Fig. 17) such as the umber (Fig. 18), the ochre (Fig. 19) and the terra verde.  The exploitation of these materials is still ongoing.

 

Umber is a dark/yellowish brown or almost black ferruginous (containing iron) sediment rich in manganese and has been used since ancient times as a pigment.  The deposits are generally earthy and friable.  The commercial deposits are widespread but generally occur as small lenticular bodies in depressions on top of the Upper Pillow Lava and at the base of the Perapedhi Formation.  Although the majority of the deposits are only 2 to 3 m in thickness, large deposits exceeding one million tonnes have historically been found.  Minor deposits also occur as inter-lava horizons within in the pillow lava sequence of the ophiolite.

 

Umber was initially thought to have been derived from weathering of iron-bearing minerals and manganese in the underlying pillow lavas.  However, all of the field evidence is consistent with an origin of umber as a chemical precipitate, which originated in the widespread activity of submarine thermal springs during the waning stages of Upper Pillow Lava volcanism.  Large volumes of metalliferous (containing metals) solutions were exhaled into oxidizing seawater, followed by umber precipitation.  Umber deposition has often been tectonically controlled and most deposits occur along fault zones.

 

The umber is excavated sporadically and transported to the factory for grinding and packing. Burning can also be undertaken to modify the colour and the burnt and unburnt mineral can be blended to achieve the required shade. It is primarily used as an industrial pigment and has excellent stability. It has also been used for centuries as an artist pigment and in ceramics and pottery, although these uses are subsidiary.

 

The ochre deposits are limited and directly associated with the sulphide deposits.  Ochre is mainly composed of iron oxides and hydroxides that give its characteristic yellowish colour.  Ochre forms during the submarine oxidation of massive sulphide ores.

 

The third natural pigment found in Cyprus is the so-called terra verde (green earth).  It has a characteristic green colour and is composed of the mineral celadonite.  It is a product of the alteration of the Lower Pillow Lavas which is found in irregular veins.

 

 

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