GEOLOGY. GEOGRAPHY.
Issue 1, 2014
CONTENTS
| Section | GEOLOGY | ||
| Codes UDC | 72+552 | Page | 50-56 |
| Title | Mineral and chemical composition of tufa and products of its interaction with environment at colonnade of the Kazan Cathedral, St Petersburg, in 2011 | ||
| Author 1 | Bulakh A. G. | St.Petersburg State University Universitetskaya nab., 7/9, St.Petersburg, 199034, Russian Federation Doctor of Geological and Mineralogical Sciences, Professor e-mail: andreygleb@mail.ru |
|
| Summary | The Kazan Cathedral is one of the most famous monuments in the center of St. Petersburg, it was constructed in 1801-1811 and designed with tufa from the settlement of Pudost near Gatchina (so called the Pudost Stone). This stone posed a number of problems for restoration workers. Tufa has calcite composition, with the pores being covered with microdruses of calcite rhombohedron crystals. Gypsum concentrates at the very surface and three reasons of origin could be named, they are: (i) chemical interaction of calcite with atmospheric SO3, (ii) plastering with alabaster, (iii) plastering with lime containing admixture of gypsum. | ||
| Keywords | the Kazan Cathedral in St. Petersburg, tufa, travertine, the Pudost stone, diseases of stone, restoration works, conservation of monuments of world heritage. | ||