Top 10 Gemstones that Occur In Only One Color
Diamond, Sapphire, Topaz, Tourmaline and many other gems can occur in different colors.But some gems can have only one color - they can only occur in different shades of the same main color.
Ruby is only red and this main color can get some orange, pink or purple tones but it's basically red.
It's only pale blue that can have some slight green-ish hues (cyan) but that's all. Aquamarine can't be red, black or brown.
It's purple/violet only. For example, you can't find a green amethyst.
A blue gemstone that comes in a variety of blue tones.
It's only pink.
It's basically blue: light to dark blue or green-blue.
I think the color turquoise (a shade of blue) was named for this stone.
An extremely rare gem that occurs only in the color you see in the image that is a mix of blue and green (call it greenish-blue or bluish green, if you wish).
Demantoids are always primarily green (by definition) but the shades of green range from a very strong yellowish green to nearly the color of a fine emerald.
Demantoid is a member of the garnet group of minerals.
Mohs scale hardness 6.5-7.0/10