This apatite is found in the "market Mine," nearby the famous Ojuela mine nearby Durango, Mexico. I have been buying these crystals for over 12 years, and finding larger crystals in good condition is difficult, primarily because the crystals are not in their original matrix, as the deposit collapsed millions of years ago. Occasionally clusters are available, and they look like someone mixed up apatite crystals in cement and let it dry. This piece has great color, and internal clarity is good. It has some micro chipping along an edge or two, and the back side has a concoidal fracture along the back length (it blends right in). It weighs 29.8 grams.