This edition of mineral testing is going to take us way back to April 2021. I will be the first to admit that a lot of life happened that delayed these results being posted. However, this was the first mineral we have sent away that took a few months of different tests to get clear results!
Photo credit: @Contempocrystals
Unlike previous individual mineral samples we have sent to the lab, this particular investigation required multiple pieces in a range of hues from lavender to blue all being sold a varieties of rose quartz. One of these pieces went by “gem” or “gel” lavender rose quartz and looked the most suspicious to the naked eye. The first round of testing involved the use of a microscope. The “gem” lavender rose quartz exhibited growth zoning, fluid inclusions, and solid inclusions of mica flakes and black oxides. Unfortunately, despite these findings being fascinating, it didn’t get us any closer to understanding where the blue hue was coming from.
"Gem" blue rose quartz
At this time the lab indicated that the fibers were too small for an optical microscope and etching by hydrofluoric acid could be more conclusive. The lab also mentioned the effect of “Raleigh scattering caused by very tiny particles may be involved in the chatoyancy and blueish hue”. The next step with these specimens, a gentle etching, proved equally inconclusive. It was then I decided to give the approval for more aggressive etching to the specimens.
This “drastic approach” was the beginning of the breakthrough we had been hoping for! The results were detectable amounts of boron in the quartz. This fit with our theory that the color was the result of a borosilicate mineral, such as one in the dumortierite family or a micro tourmaline, causing the hue! Our friend at the lab had another very cool experiment to try to dig deeper. He planned to gently etch the material and preserved the fibers in a hydrothermal pressure vessel. SO COOL! It took 2 failed attempts using different chemicals for this process until he finally hit on one that WORKED! After all that dedication of time and isolating the fibers after 3 days in hydrothermal fluid, he was able to photograph the culprits. Extremely small dumortierite fibers coupled with consistent Titanium and Iron content is what gives these beautiful pieces the blue hue.
Photo Credit: @j_e_quim