Aquamarine- (Beyrl)- composed of beryllium aluminium cyclosilicate with the chemical formula Be3Al2(SiO3)6. ....The pale blue color of aquamarine is attributed to Fe2+ , hardness of 7.5–8, Crystal system Hexagonal
Nickel is a chemical element with the atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile. It is an alloy metal used in many specific and recognizable industrial and consumer products, including stainless steel, alnico magnets, coinage, rechargeable batteries, electric guitar strings, microphone capsules, and special alloys. It is also used for plating and as a green tint in glass.