A milial cyst is a small, keratin filled cyst, often found on the face. This lesion is quite common in women who apply moisturizers, and can also be a complication of facial cosmetic dermatology such as dermabrasion, chemical peels, and laser resurfacing.
The hardened keratin sounds like a grain of sand embedded in the tissue, making a scraping sound at each pass of the blade.
In these sections, you can see the stratified layers of keratin lining the cyst.
