Carletonite is a rare mineral that was first discovered in Canada. This mineral is usually found in dark blue to black crystals that can be quite stunning. Since carletonite is so rare, there aren't many synonyms for this mineral. Some possible alternatives might include blue calcite, blue apatite, or blue tourmaline. These minerals can have similar colors and appearances to carletonite, but they are not the same thing. Other minerals that might be mistaken for carletonite include azurite, chalcanthite, and vivianite. However, each of these minerals has its own unique characteristics and properties that set it apart from carletonite.