#i started a new gemmology post to answer your question so i don't have to keep reblogging that offensively colourful gem photo series ^^;

[just-here-with-my-thoughts]

@theproblemwithstardust stabilising treatments in beryl var. emerald

*picture from ⁣Emerald Enhancements - A Guide to Treatments for Clarity in Emeralds | The Natural Emerald Company

The beryl family of gemstones (beryllium aluminium silicate, hexagonal crystal system) provides a number of gem species depending on its colouring element, each with different characteristics

Emerald, green, coloured by Chromium

Aquamarine, greeny-blue to blue, coloured by Iron

Heliodor, yellow, coloured by Iron

Morganite, pink, coloured by Manganese

Green Beryl, light green, coloured by Vanadium

Red Beryl, red, coloured also by manganese maybe but I don't actually remember off the top of my head ^^;

Goshenite, colourless, no trace elements causing colour

Many of these varieties can grow large, very clear crystals free from inclusions. However emerald is typically more heavily included as the chromium atoms in the crystal structure are larger, leading to different growth conditions.

Emerald clarity should be judged against other emeralds, not against other gemstones or even other members of the same gem species! A 'high clarity' emerald is still likely to contain eye-visible inclusions, whereas the same inclusions in an aquamarine would be considered moderately included.

Fissures in emerald can be unsightly as well as causing durability issues. It is incredibly common to impregnate emerald with oil to fill the fissures, partly to improve durability and also to increase the visual appeal of the stones (as the oil filling reduces the visibility of fissures). As this is an historic treatment it does not require disclosure* - it is accepted that most if not all emeralds commercially available will have been oiled.

In more recent times fissures can also be filled with natural or artificial resins, which have been developed to have a very similar refractive index to emerald thereby reducing the visibility of the treatment, and the surface wiped with a hardener to set the treatment. In practice this is also an accepted treatment*, unless the impregnating material also contains dye to improve the colour of the stone, at which point it must be sold as treated 'dyed emerald'.

Impregnation/fracture filling of emerald brings many stones to the market which would otherwise be considered unsaleable and should be viewed as a positive step to increase availability of gem-quality material. That said, filling treatments are not permanent and oils can be lost if the emerald is not carefully handled during cleaning and repair work. It is possible for emeralds to be re-oiled but it is best to avoid cleaning techniques such as ultrasonic cleaners in the first place.

**please note the law regarding disclosure of treatments may vary by region, this is a fun information post about gemstones and not a guide to international trading standards!

Side note - although it isn't a treatment, there are other things you can do to ensure your relatively brittle emerald receives the best care! Choice of cut is one such thing. Ever heard of 'The Emerald Cut'? This octagonal step cut style was developed both to maximise yield from rough emerald crystals, and to protect the corners from chipping by making sure there are no right angles which would be prone to being knocked and chipped!

Cabochon cuts are also considered a protective cut style, however these would typically be used on more heavily included material, with popular faceted styles reserved for high-quality stones.

just-thoughts-about-gems (this is the place to ask your gemstone questions)