"Cobalt Teal is a high performance cobalt pigment developed during the 20th century but the colour itself as an artists colour is much more ancient. It is similar to the colour of the best quality turquoise stone which was mined in the Sinai and was crushed and processed to produce this gorgeous turquoise colour. Since it was made directly from gemstones the colour was fabulously expensive but since all art in ancient Egypt was made by artists and scribes in the employ of the temples and pigments were therefore ultimately paid for by the pharaoh cost was no object. Its name was mefkaht and it had an impressive hieroglyph that included the symbols for Horus, a viper, outstretched arms, the rising sun, and 3 grains of sand. Light green pigments generally were used to represent joy but turquoise was considered to the most important of these pigments and embodied promise and omens for the future. It was the colour used to represent the rays of the rising sun and was said to be the colour of the eye of the god Horus. It was also the colour of Hathor who was the goddess of new born babies. One of her names was The Lady Of Turquoise. Clearly this colour had huge meaning for the ancient Egyptians but after the fall of the Roman Empire turquoise pigment production fell into decline and in Europe there was no turquoise colour like this available to artists until the 20th century.
Cobalt Teal is a true turquoise colour much like the gemstone. There are many other colours available now that are called turquoise because we tend to apply it to any colour midway between green and blue but only Cobalt Teal is like the original colour used by the ancient Egyptians. Unlike those ancient people, however, who never mixed the colour with any other pigment but used it pure, the modern artist is liberated to used this colour to its full potential and it is very useful, especially for making greens but it has a couple of additional surprises up its sleeve.
Because Cobalt Teal can be considered simply as a light greenish blue one of its strengths is making light greens and some of them are quite unique and cannot be made with any other pigment. Mixing Cobalt Teal with Nickel Titanate makes the most delightful light apple green that is quite luminous while mixing it with Permanent Green Light makes gorgeous jade greens. A surprising bright yellow green is the result of a mixture with Cadmium Yellow Medium. Soft grey greens are made by mixing with either Transparent Red Oxide or with Hookers Green. These grey greens are a lot like the colour of blue gum leaves in the shade.
Blues can also be interesting when made with Cobalt Teal. Try mixing with Australian Red Violet. It seems an unlikely combination but it makes a slightly neutralised dark reddish blue that is unlike any blue in a tube. A very pale grey-blue can be made by mixing Cobalt Teal with Ash Pink. Iridescence holds surprises too. Cobalt Teal with Iridescent white or Metallic Light Gold are delightful. In the end, however, few colours can match the beauty of this colour straight from the tube and used pure just like the ancient Egyptians would have.