As the popular saying goes, diamonds are a girl's best friend. But does the precious stone, often used in cosmetic products, offer any real beauty benefits? 

Well, celebrities like Mila Kunis have reportedly been treated to facials using jewels, inspiring us to believe in their power. Who wouldn't want to shine bright like a diamond? Beauty junkies can buy serums, masks, BB creams, nail polishes and even shampoos containing the stones nowadays. But many of the products come with expensive price tags.

If you're willing to pay the costs, get ready to enjoy a few fabulous benefits. 

First, finely ground diamonds are great for exfoliating. Cosmetic dentist, Dr. Emanuel Layliev applies a scrub, containing diamond dust, to teeth before performing whitening procedures. Why? Following that guideline opens the teeth's pores. 

"The diamond powder exfoliates very gently to remove the surface stains right before the whitening," said Dr. Emanuel to the The Cut.  "It opens up the enamel pores in order to allow better penetration of the peroxide so that it can break down the stain molecules that are deeper." 

Consumers can also buy exfoliating scrubs, containing diamond powder, that kill dead skin cells for at-home use. Women can treat themselves to smoother skin, which is more resilient and radiant.

But going with diamonds does have its drawbacks. Ron Robinson, a cosmetic chemist and the founder of BeautyStat, believes that shoppers can get the same effects using a less-expensive product. "There are other types of exfoliators that work just as well," said Ron. "The manufacturers are spending more to put it in the product, and they're then able to command a higher price for it."

Beauty lovers looking to buy products using diamond powder as a brightener and optical diffuser should be careful in making purchases. Items with the finely crushed stones promote luminosity, but "it's not the best brightener that could be used in skin care," added Ron.

Randy Schueller, a cosmetic chemist and editor at the Beauty Brains, said that products must have about 5 percent powder to cause luminizing effects. But most buys on the market don't contain that much of the formula.

And the benefits that you get from the powder are only temporary. Since diamonds are an inactive ingredient, and never penetrate your skin or pores, they will not provide any long-term solution to a beauty problem.

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