Where did you find it? Is it magnetic? Try a streak test as well. Some better pictures, close ups in good light, may help. The blue background is not helping the contrast as it appears blue on blue with the sample.
Streak test is to see the color of the mineral by rubbing it on a white porcelain tile. It can also give an indication of hardness of the mineral. Pics are better but nothing definitive in it that I can see. Galena is a possibility.