Denim gray-blue cabochon of Indian Sapphire. It has not only a universally suitable color (almost everyone wears jeans) but above all hardness!
The color is natural.
The sapphire is a stone of kings, and its blue variant belongs to the most sought-after (and also the most expensive in the case of transparent versions) gems in general, it belongs to the stones of the third eye, ie to the sphere of decision-making and intuition. It is a very strong stone, like all corundum. (it is also very hard)