Gorgeous fluorite from classic and famous locality Boltsburn mine, County Durham (UK). Old piece collected early XXth century, its color changes a lot according to light variations as you can see in pictures. Bought years ago to minerals dealer and collector Martin Gruell who described the fluorite "A very old specimen from Boltsburn. The former owner unpacked it from a news-paper of 1943 ! The crystals are highly lustrous, they show very nice texture and grey-blue color. The dark siderite matrix in the center helps to give nice contrast to the piece" Measurements : 5 x 4,5 x 4 cms Weight : 70 gr IMPORTANT : I am a reputable art dealer with a high level minerals collection I don't use PHOTOSHOP to improve the color, i hide nothing, i use different lights to show the piece perfectly, you see all the sides !! WHAT YOU SEE IS WHAT YOU GET !! The first photos have been taken by professional photographer (artificial light), the last ones outdoor (only natural light)