Star-Fleetís recent contest with the crystalline entity has reminded the author of his own encounter with a crystalline entity as part of the AET.
There is a precedent for Start-Fleetís study of the crystalline entity. Another type of crystalline entity was encountered on Earth in the 20th century. Existence of this crystalline entity has been kept secret in order to protect it, and people.
AET was called to investigate a cavern discovered by a vacationing spelunker. He noted in particular unusual and disorienting optical displays refracted from crystals in the cavern.
Apparently the Earth has itís own crystalline entity in the form of intelligent diamonds called the Diamonello by the author. Found somewhere in the Rocky Mountains, in an underground cave where there is little light, is a growing organism which is based on an impure diamond lattice. It was discovered that this organism was both alive and intelligent. Unlike DNA based life-forms, the Diamonello are made up of carbon crystals (diamonds). It is a carbon based life-form although an unusual one. Upon entering the cave and shining a light, the Diamonello is able to rearrange the light from the flashlight into an intelligent display which is projected onto the cave wall. It is possible to communicate with the Diamonello using visual images. The Diamonello is highly intelligent, covering several acres of underground cavern floor. The Diamonello is billions of years old, and grows at a glacial rate.