Brian Berger, a Gemological Institute of America (GIA) graduate and Philadelphia investment company CEO, recently purchased the unlikely insect-opal, a formation many scientists thought was impossible due to the gemstone’s slow-forming process.
The specimen was already deemed an extremely rare find featuring a ‘play of color’ throughout the stone, but the fossilised insect has made the opal particularly unusual.
Upon close inspection, Berger said the insect appeared to have an open mouth and remained well-preserved, with fibrous structures extending from the appendages.
“Further research is being conducted on the specimen currently. The initial theory is that this encasement may mean the opal itself is opalised amber,” Berger said, writing for entomologytoday.org.
“Theoretically speaking, the insect likely was trapped in tree sap or resin which, over time and under the right circumstances, was preserved as amber with the insect encasement. However, a second, much rarer process of opalisation can also occur.
"And so, in this case, as conditions changed for the amber specimen, it is possible the amber opalised, preserving the inclusion. Amazingly, the silica surrounding the insect also structurally changed to produce the ‘play of color’.”
The GIA recently examined the opal and awarded a letter of provenance for the rarity of such an inclusion. The letter includes the GIA report number from the examination.
“From a gemmological standpoint, this is truly an exciting and extremely rare, notable find. And the same can likely be said from the entomological perspective. In the future, I would be eager to collaborate with an expert in insect fossils to investigate the insect inclusion further,” Berger said.