A dark blue is the most desired color,Lower qualities are heated to change them to the desired aquamarine blue.  It is brittle and sensitive to pressure. It is more frequently transparent than emerald. The pigment is iron. Typical inclusions are fine hollow rods which sometimes reflect white light. Where growth lines are present in larger numbers, a cat’s eye effect or even asterism with a six-rayed star is possible.
Because of inclusions of foreign substances, physical properties can vary. The maxixe aquamarine from Brazil has quite different constants. It is rarely used any more because the color apparently fades in daylight.
There are aquamarine deposits in all continents. The most important ones are in Brazil. The host rocks are pegmatite and coarse-grained granite. Numerous finds have been made in the inner highlands of the Malagasy Republic, The well-known deposits in Russia.
Large crystals are comparatively common and can weight up to 110kg. The preferred cut is emerald or scissor cut with rectangular or long oval stripes.
We love to use it raw, rough.

*info by Walter Schumann “Gemstones of the World”