Karlite (kar'-lite) is a silky white to light green orthorhombic borate mineral, not to be confused with tremolite-actinolite.

[4] Karlite is named in honor of Franz Karl (1918–1972), professor of mineralogy and petrography at Christian Albrechts University in Kiel, Germany, for his studies of the geology of the eastern Alps.

Karlite possesses moderate optical relief, the degree to which the mineral grains stand out from the mounting medium.

Karlite is a relatively newly discovered borate mineral occurring in clinohumite-chlorite marble in calcsilicate-carbonate lenses embedded in amphibolite.

[5] This mineral was originally discovered in the Furtschaglkar near the Furtschaglhaus in Austria, but has also been found in Russia and France, and was probably formed during the alpine metamorphism of the Alps.