On an expansive campus with plenty of hidden treasures, Snee Hall's mineral and gem room really is a trove of shiny things.

The Timothy N. Heasley Mineralogy Museum, in the lobby of Snee, hosts several collections of the Earth's naturally occurring crystalline solids known as minerals, of which about 4,000 have so far been discovered. Popular minerals abound -- the brilliant purple amethyst, for instance -- while others are as exotic as their names suggest, such as kammererite (which also happens to be purplish).

The pieces, arranged according to mineralogy's Dana classification system, have been acquired by the Department Earth and Atmospheric Sciences in stages over the years, with such benefactors as Yale chemist Benjamin Silliman, George Kosel '44 and Albert Podell '58 donating their collections.

Most recently, professor emeritus of geological sciences Bill Bassett, the museum's curator for the past 30 years, and his brother, Allen Bassett, added an impressive array of both rough and faceted gemstones, which take up a generous portion of the museum's middle display case.

Tourmaline, emerald, aquamarine, topaz and corundum -- the mineral name for ruby -- are just a few of the gems on display in the Bassetts' collection, along with a rough piece of black opal that Bill Bassett said belonged to his grandfather.

Visitors are often drawn to the glass replicas of well-known diamonds, including the 726-carat Jonker diamond, the 245-carat Jubilee diamond and the famously blue Hope diamond, which weighs in at 45 carats and whose authentic counterpart sits in the Smithsonian Institution in Washington, D.C.

Even more stunning than look-alike diamonds is a rare nugget of gold that sits in its own case near the museum's entrance. The specimen was collected in 1865 from California gold country.

"That is the finest piece of gold in the collection," Bassett said. What makes it fine is that it actually has crystals of gold, which are quite rare."

One corner of the museum is occupied by a small collection under an ultraviolet light, which unveils those particular minerals' fluorescent properties. For comparison, the minerals are also displayed in normal light. A dour-looking, yellow piece of autunite glows a brilliant green in the ultraviolet wavelength, due to its composition as a uranium phosphate.

The museum was named for the nephew of Katherine Snee, whose husband, alumnus William Snee, bequeathed the funds to build Snee Hall, which was completed in 1984.