(December 2008) Yellow discoloration in Oslo’s opera is seen as an indication of progressive damage to the Carrara-Marble according to geology professor Tom Anderson. It shows that the mechanical stability of the marble is in a state of transition, making a replacement necessary within a few years. (Norwegian). Findings were preceded by considerable contention at the implementation of this class of stone emanating from the warm climes of northern Italy. After all, cases were documented in Finland, in which Carrara-Marble had not withstood the harsh climate.
Minerals have undergone a process of evolution, according to American scientists as reported in the scientific journal American Mineralogist (Vol 93, pp 1693-1720, 2008). By this, scientists do not mean to suggest that minerals changed over time by means of mutation or promulgation. Rather there is a tendency to develop new types – provided the environmental conditions are conducive to change. Scientists have identified ten levels of evolution over millions of years. One was the appearance of volcanic activity and water. Together they allowed for hitherto unknown chemical and physical processes making room for new minerals to develop – conditions shared only with Mars and Venus. Another step was the release of oxygen into the atmosphere exposing minerals to oxidation which plants and microorganisms processed to clay.
An impressive 365 years old – that is the anniversary celebrated by the French stone-tool manufacturer Guillet S.A. The company originally set up shop in Villebois between Lyon and Geneva in 1643 as a smith working for the stone industry of the time. The big time celebration on the company grounds included setting up a monumental monolith of local stone, 10 x 3 x 1 m and weighing 86 tones; a 7,50 m stone gateway was set up at the entrance of the complex carrying the inscription of the company name in 60 cm letters. 1889 saw the erection of a 9 m, 42 t pyramid in the town of about 1000 inhabitants commemorating the 100th anniversary of the French Revolution.