On the way I ascended a small hill composed of mica slate, and on its summit found two or three specimens of tourmaline.
The "tourmaline's" men appeared highly delighted at our defeat.
The dichroism is feeble too, whereas that of tourmaline is strong.
I can't resist this tourmaline, and have carried it off with me.
We may begin the study of the polarization of light, with ease and profit, by means of a crystal of tourmaline.
tourmaline smiled and shook her head, while all the Counselors murmured their protests.
Zircon, tourmaline, garnet and other precious stones of little commercial value are found throughout Australia.
Two Nicol prisms play the same part as the two plates of tourmaline.
Jargoon and tourmaline, when cut as gems, are sometimes mistaken for each other, but the sp.
Let us take, as an example, the crystal of tourmaline, with which we are now so familiar.
complete silicate of aluminum and boron, 1759, ultimately from Sinhalese toramalli, a general name for cornelian.
Any of several minerals having the general chemical formula (Na,Ca)(Mg,Fe,Al,Li)3Al6(BO3)3Si6O18(OH)4. Tourmaline occurs in many different translucent colors, usually in crystals shaped like 3-, 6-, or 9-sided prisms. It occurs in igneous and metamorphic rocks, especially in pegmatites.