Kunzite crystals display two interesting phenomenon, pleochroism and perfect cleavage, both of which need to be considered when cutters orient the gem for finishing. Cleavage refers to a stone’s tendency to ‘cleave’ or ‘split’ along certain crystallographic structural planes due to a weakness in their atomic bonds. Many stones present perfect cleavage including topaz, diamond and fluorite. Although a gemstone doesn’t necessarily become weak because of perfect cleavage, the gem cutter and jeweller must practice caution to ensure cleavage does not occur. In kunzite’s case, the cleavage occurs in two directions, one being parallel to the length of the crystal in line with the surface striations.
Pleochroism refers to a stones ability to display different colours in different crystal directions. Kunzite crystals exhibit strong pleochroism with the best/ darkest colour visible when you look down the length of the crystal. Due to these two factors this beauty is considered a real gem cutters challenge.
Bunny Bedi, owner and director at Made In Earth, discusses the difficulties with dealing in kunzite. “We source our kunzite from the Pakistan/Afghanistan border and they have become increasingly harder to source. Pre-cut stones are scarce as 15%-20% is the maximum yield we can obtain from the rough and this is the same reason why we don’t cut stones ourselves. It’s a tricky stone to deal with because of its brittle nature and pleochroic attributes although when we do get faceted stones they display a significant dispersion/brilliance and they’re absolutely breathtaking. These days we tend to keep the crystals in their natural state and create pieces that show off their well formed crystal structure.”
Oozing femininity and grace, pink stones have always had an alluring quality. You don’t need to be a girly-girl to appreciate something as magical as a brilliant pink gemstone. Named in honour of pioneering gemmologist Dr. George Frederick Kunz (1856 – 1932), Kunzite is the prettiest of the spodumene crystals in delicate shades of pink and lilac. The heart wants what the heart wants and my heart beats for this magnificent beauty.
First discovered in the Pala district of San Diego California, today these beautiful crystals are mainly found in Afghanistan, Madagascar, Brazil and USA. Sister to the yellow/green mineral called hiddenite; spodumene crystals are long, prismatic and heavily striated parallel to the crystal axis.
Crystals are generally well formed and can be found in large sizes weighing over 1 kilogram. Their hardness is fairly good ranging from 6.5 – 7 on MOH’s scale although their attribute of perfect cleavage means they’re not necessarily ‘tough’ crystals. A known source of lithium, kunzite’s composition can be expressed as LiAl(SiO3)2 and owes its pink hues to trace elements of manganese.
“This precious gem is precious in every sense of the word. We like to advise our clients to pay special attention to these pink stones to ensure that they’re handled with care and protect them from exposure to great heat or bright sunlight to make certain that they don’t fade and lose their colour.”
Rare and beautiful, kunzite’s delicate nature is matched by its delicate colour… certainly pretty in pink!