Sulfur, which is given a bad reputation because of its odor, can make a very beautiful mineral specimen, and fine quality examples are much sought after. The unmistakable deep yellow color is not matched by any other mineral and the nicely shaped crystal forms of sulfur add to its attractiveness. As for the odor, this occurs when water mixes with the sulfur and a small amount of hydrogen sulfide (H₂S) gas is produced. Although only small amounts of H₂S form from just moisture in the air, it is a powerful odor producer and is the dominating contributor to the odor of rotten eggs. Rest assured, though, that most specimens of sulfur, when kept dry, do not emit a strong odor and this is not difficult for collectors of fine sulfur specimens to ensure.