Ruby Consumer Information
Care
Rubies are extremely durable due to their hardness and toughness – second after diamond on the Mohs Hardness Scale. Ruby jewellery may be cleaned in an ultrasonic cleaner, or it may be steamed. But this should follow close inspection to determine if there are any surface reaching fissures that could expand, or if oils or dyes are present. As with most gemstones, a soft moistened cloth, or a soft bristle toothbrush may be used to clean the gem
Treatment
Transparency: heating dissolves or partially dissolves fine rutile needles thereby increasing the clarity and transparency of the gem.
Transparency: High lead content glass is sometimes used to fill surface reaching fissures, pits or cracks in certain rubies/ corundum increasing transparency
Color: heating helps remove purplish or brownish colour components in some gemstones, resulting in stronger red colours
Color strengthening: diffusion of colour causing elements through intense heating
Color
Color and transparency: heat treatment (partially) dissolves fine rutile needles thereby increasing the clarity, transparency and remove brownish components
Color strengtening: diffusion of colour causing elements through intense heating
Color: surface reaching fissures may be treated with oil or dyes, resulting in stronger colours. Treatment not durable and requiring special care
Improving transparency: lead glass filling in cavities and fissures
Clarity
“Silk,” networks of fine, included rutile needles, intersecting at 60 degree angles, are commonly seen in natural ruby
Included crystals of zircon, and related stress fractures (or halos) are sometimes seen. Liquid-filled “fingerprint” inclusions are also common
Note some of these identifying characteristics may disappear, change or be diminished as a result of treatments
The presence of silk or other inclusions is often valued since it not only points to a gem’s natural origin but it also suggests the gem has not been treated
Cut
In the market, rubies are found in a variety of shapes and cutting styles
Ovals are cushions are the most common, but rounds are also seen, as are other shapes, such as the heart or emerald cut
Slight premiums are paid for round stones, while slight discounts apply for pears and marquises
Stones that are overly deep or shallow should generally be avoided