Howlite: This calcium silicoborate  is typically an opaque white to grey, with grey to black streaks in an erratic, often web-like pattern. Howlite is named after mineralogist Henry How, who first discovered the gemstone in Nova Scotia during the 19th century. It has a Moh’s scale hardness of 3.5, and because it is easily dyed, it is most commonly used to simulate more expensive gemstone varieties such as Turquoise and Lapis. North America is the world's primary source of Howlite. It is said that Howlite is the stone of memory, knowledge and progress, and is claimed to encourage reasoning, observation, discernment, patience and tact. It also is believed to eliminate pain, stress and anger, and help balance calcium levels in the body, aiding in absorption and distribution.