Diamonds might be a girl's best friend but just wait until they set eyes on extremely rare Sardinian ichnusaites. Forget the chocolates and the flowers and if you're looking for a truly rare ring to give your fiancée, forget the diamonds.

More precious than emeralds or diamonds, scientists came up with an initial list of rare minerals that can soon become the best exotic gifts for Valentine's Day.

The initial list of 2,550 rare minerals includes truly rare finds such as ichnusaite, amicite, fingerite and nevadaite. These can be found from only five or fewer locations around the world unlike diamonds that are plentiful when compared to these truly rare finds.

Apart from the few locations, extremely rare conditions are needed to form the minerals including exact temperatures. Some rare minerals only form with other unique elements while some form inside volcanoes and can easily be dissolved.

A team of scientists who prepared the list said that rubies, emeralds, diamonds and other gems can be found in many areas around the world and are sold in large quantities commercially. Therefore, these are not really rare.

Co-author Robert Hazen said that if you're looking for the perfect and rare ring for your fiancée, forget the diamonds and give her a ring with a truly rare Sardinian ichnusaite. Hazen, who is from the Carnegie Institution, said that some of the rare minerals included in their initial list are known to have only a thimbleful quantity found.

The 2,550 minerals included in the initial list might have commercial uses. If they can be manufactured, the minerals can also be used in batteries and electronics.

"Some minerals are rare because, even though they form from the commonest of ingredients, they must be cooked at exquisitely controlled conditions," added Hazen.

Currently, there are 5,090 known minerals around the world. About less than 100 make up 99 percent of the planet's crust. The researchers said that about 1,500 minerals are still left to be found and of course, there are master jewelers who would grab the opportunity to work with rare minerals.

The findings were published [pdf] in the American Mineralogist journal.

Photo: Timothy Marsee | Flickr