Reference:
▪ Biagioni, C., Bonaccorsi, E., Merlino, S. (2010): Crystal structure of bultfonteinite, Ca4[ SiO3(OH)]2F2·2H2O, from N'Chwaning II Mine (Kalahari manganese field, Republic of South Africa).
Atti della Società Toscana di Scienze Naturali, Serie A,
115, 9-15.
Abstract:
The finding of well-crystallized specimens of bultfonteinite from the N’Chwaning II mine (Kalahari Manganese Field, Republic of South Africa) in the 1980s allowed the collection of new data about the crystal structure of this calcium silicate hydrate. The crystal structure study is in agreement with the general features outlined by McIver (1963) and allows the description of a reasonable hydrogenbond scheme.
The refined cell parameters are
a 10.999(1),
b 8.176(1),
c 5.6678(5) Å, α 94.24(1), β 89.00(1), γ 90.18(1)°,
V 508.2(1) Å3, space group
P-1.