Resin filling is filling a gem's fissures or cavities with a resin, often one that hardens, to hide them.
In more detail
It is common in emerald. Resin can deteriorate over time. A colored resin also changes the color, and the lab then reports a colored filler.
On a grading report
Fissure filling with its amount (F1 to F3), or cavity filling (C1 to C3). A colored filler is reported as such.
Related terms
- Clarity enhancement: Clarity enhancement is filling surface-reaching fissures with a filler such as oil, resin, wax or glass, so they show less.
- Emerald oiling: Emerald oiling is filling an emerald's fissures with a colorless oil to make them less visible.
- Manufactured product: A manufactured product is a gem held together by glass or resin. It is made from badly fractured rough, or from many small pieces bound into one.
- Enhancement degree: The enhancement degree is the amount of filler a lab finds in a gem's fissures: minor, moderate or significant.