
Azurite is one of the two most common copper minerals [the other being Malachite], and has been popular throughout the ages for its rich blue coloration.
It often forms small, druzy crystals that encrust a cavity or a crack in a rock, and can often be found with malachite, as in the picture above - the contrast between the blue and the green makes for strikingly beautiful specimens.
It is sometimes used in jewelry, but bright light, heat, and even exposure to air cause it to deteriorate, reducing the color.
If heated, it will turn an ugly sort of black, which means that any sort of jewelry construction using azurite must be done at room temperature. It is also rather soft, and therefore easily damaged.
In the Middle Ages, azurite was commonly ground up and used for blue pigment in paints, as it was a more obtainable alternative to ultramarine [which was made from lapis lazuli].
Unfortunately, paints made from azurite tend to turn green as the years go by, so the colors in many of the famous old paintings we've all seen actually bear little resemblance to how they'd look if they were fresh!
A famous example of this is the Mona Lisa - click here to see the original along side the color-corrected version. It's quite a difference, isn't it?
Since lapis lazuli was primarily supplied from Afghanistan at the time, it tended to fetch very high prices. And as azurite was a common mineral throughout Europe, the flaws of azurite as a pigment were often overlooked.
Next time you look at a famous work of art, you could be looking at a little piece of mineralogical history as well.
It often forms small, druzy crystals that encrust a cavity or a crack in a rock, and can often be found with malachite, as in the picture above - the contrast between the blue and the green makes for strikingly beautiful specimens.
It is sometimes used in jewelry, but bright light, heat, and even exposure to air cause it to deteriorate, reducing the color.
If heated, it will turn an ugly sort of black, which means that any sort of jewelry construction using azurite must be done at room temperature. It is also rather soft, and therefore easily damaged.
In the Middle Ages, azurite was commonly ground up and used for blue pigment in paints, as it was a more obtainable alternative to ultramarine [which was made from lapis lazuli].
Unfortunately, paints made from azurite tend to turn green as the years go by, so the colors in many of the famous old paintings we've all seen actually bear little resemblance to how they'd look if they were fresh!
A famous example of this is the Mona Lisa - click here to see the original along side the color-corrected version. It's quite a difference, isn't it?
Since lapis lazuli was primarily supplied from Afghanistan at the time, it tended to fetch very high prices. And as azurite was a common mineral throughout Europe, the flaws of azurite as a pigment were often overlooked.
Next time you look at a famous work of art, you could be looking at a little piece of mineralogical history as well.