Howlite (also known as magnesite) is a white stone with gray or black matrix like inclusions.  The dyed howlite is marketed as turquenite and is commonly used to make jewelry components. Because of its porous texture, howlite can be easily dyed to imitate other minerals, especially turquoise for the superficial similarity of the veining patterns. Howlite is a super-calming stone and many people use it to relieve stress of all kinds.