Thermal Behavior of Howlite, Ca2B5SiO9(OH)5

L. A. Gorelovaa, b, M. G. Krzhizhanovskayab, and R. S. Bubnovaa, b, *
Translated by G. Levit

aGrebenshchikov Institute of Silicate Chemistry, Russian Academy of Sciences, St. Petersburg, 199034 Russia

bSt. Petersburg State University, St. Petersburg, 199034 Russia

Correspondence to: *e-mail: rimma_bubnova@mail.ru

Received 17 April, 2017

Abstract—The thermal behavior of natural borosilicate howlite, Ca2B5SiO9(OH)5, is studied by the methods of high-temperature X-ray diffraction and differential thermal analysis in the temperature range of 30–1100°C. The thermal expansion is anisotropic (αmaxmin = 3.6); the degree of anisotropy increases (αmaxmin = 4.3) with a temperature increase up to 480°C (360–480°C).

Keywords: howlite, borosilicates, thermal expansion

DOI: 10.1134/S1087659617060037