What do the two things in this picture have in common? They're both tourmaline, yet obviously in different forms. Tourmaline is a chemical combination of primarily silicate, boron, and aluminum (but sometimes includes other elements like iron, magnesium, and lithium). This precious crystal is ground down into a fine powder and then added to hair tools such as "infused" into a ceramic coated flat iron, applied in a thin coat on top of the brush or ground up to coat the inside of a dryer.
Even though both my hair brush and flat iron feature this substance, quite honestly that wasn't my deciding factor for purchase. Still, I was interested to learn about the added benefits. Turns out that tourmaline plates produce around six times more negative ions than standard ceramic plates. (Negative ions straighten your hair for far longer and give it a silkier, shinier look.) Tourmaline products are typically smoother than the ceramic versions — they create less friction and damage from styling, and in the end get smoother results.