Stones

Man-Made Stones

– are a human invention and created within a laboratory. A man-made stone has no natural counterpart.

Synthetic Stones

– are made by technicians in a laboratory under controlled conditions. In order for a stone to be termed synthetic, it must have a genuine, natural counterpart. Essentially, synthetic stones have the same chemical composition, crystal structure and optical and physical properties as their natural equivalent.

Natural Stones

– are minerals, stones or organic matter found in nature and formed naturally over time, without the intervention of man.

Measuring a Stone’s Durability

A stone’s durability is an important factor in determining which type of jewellery it is best suited to, as well as an indication of the care with which a stone should be treated with. Gemstone durability is measured in three categories: hardness, toughness and stability.

Hardness

Hardness is evaluated as the stone’s ability to resist scratches. The Mohs scale is industry standard to rate hardness. It was created in 1822 by Friedrich Mohs who selected ten minerals and assigned numbers to them, based on the relative ease or difficulty with which one could be scratched by the other. The scale ranks minerals from one to ten, with ten being the hardest. Each mineral has the ability to scratch all the minerals with lower rankings on the scale. It is important to note that the scale is ordinal, defining the position of gemstones in a particular series (e.g. first, second, third, etc.) rather than directly comparing the relative differences between the minerals. For instance, diamond is just one number above corundum (sapphire and ruby) on the scale, but is actually much harder. If the hardness of a stone is between two numbers on the scale it is expressed by adding ‘0.5’ to the lowest number

Toughness

Toughness is measured by how well a stone resists breaking, chipping or cracking on impact. Every stone, even a diamond, will fracture if it is hit hard enough. Toughness is rated as either poor, fair, good, excellent or exceptional.

Man-made and synthetic stones, natural gemstones, pearls and diamonds, are all used in Pandora jewellery.

Stability

A material's ability to be altered by exposure to light, heat or chemicals, stability is also a measure of a durability. Many stones should not be exposed to acids and some, such as amethysts, are light sensitive, fading if exposed to strong light for long periods. Stones that contain water, such as opals, can become dehydrated and crack, and sudden temperature changes can induce thermal shock in some others, resulting in cracks or fractures.

Treatments

Treatments are a way of refining a stone’s appearance and are comparable to the way in which other natural materials, such as leather and cotton, are treated through processes such as tanning, bleaching or scouring.

BLEACHING – lightens and whitens gems such as pearls.
DIFFUSION – adds colour to the surface of colourless gems, while the centre remains colourless.
DYEING – adds colour and improves colour uniformity in stones and pearls.
FRACTURE FILLING – injects colourless plastic or glass into a stone to hide cracks or fractures and improve the stone’s clarity and durability.
HEAT – lightens, darkens or changes the colour of stones or improves clarity.
IMPREGNATION – improves appearance and diminishes imperfections by adding colourless oils, wax or resins to a stone.
IRRADIATION – deepens or adds colour to coloured diamonds, stones and pearls.
LASER DRILLING – removes dark inclusions from diamonds to improve clarity.

Treatment Disclosure

Pandora is a certified member of the RJC. Pandora complies with relevant rules and regulations regarding the correct marketing and declaration of stone treatments. The following types of treatments must always be disclosed to customers: 1) Non-permanent treatments. 2) Treatments which create special care requirements (applies to both man-made, synthetic and natural stones). 3)Treatments which significantly affect a (gem)stone’s value Pandora uses treatments such as heat or bleach to improve stone clarity, as well as surface waxing to promote shine. All treatments are specifically disclosed with the word “treated” unless the result is permanent under normal conditions and requires no special care, and provided that the treated stone cannot be visually confused with its untreated counterpart.

freshwater cultured pearl

The freshwater cultured pearl is an example of organic matter that is formed naturally over time.

Care Recommendations

Listed under each stone are the corresponding care recommendations.

Normal Care - Avoid rough handling and when not in wear, store items of jewellery separately to avoid scratches. Clean with warm, soapy water and gentle brushing. Ultrasonic cleaners should only be used with caution.

Special Care - In addition to normal care, some stones have special care requirements. These care requirements are noted under the relevant stone.