Results found: 1

Search results

Search:
in the keywords: fluoryt

Sort By:

Limit search:

Fiolet "śląski" : identyfikacja nie znanego pigmentu w gotyckim malarstwie ściennym na podstawie materiału uzyskanego w czasie prac konserwatorskich w latach 1978-1985

100%

Wisła E., Żurkowska-Mastalerz T.

Ochrona Zabytków

1987

issue 4

312-318

The observations and results of studies presented in this article have been compiled during the uncovery and conservation of Gothic mural paintings. Violet colour was found in three subsequent objects. The samples on the basis of which a violet pigment has been identified come from the paintings on the vaulting of Holy Cross’ Chapel in Lwowek Śląski and from the vaulting of the Getliczs tomb chapel at Lipa (1498 and ca 1500). It has been found out during the work that the pigment has not undergone changes due to some destructive factors, which is the usual case with other pigments such as green, blue and red. For obvious reasons only minimum samples have been taken, strongly soiled with whitewash (calcium carbonate and silica) and residues of adhesives and dust. All the analyses have been made without separating the components in order not to destroy the samples. The first examinations have been done in the Academy of Fine Arts in Cracow (optical microscopy and emission laser spectroscopy) ; they suggested glaze and ochre. This did not however explain the origin of the colour. Further identification studies have included: 1. Quality analysis of the chemical composition by means of X-ray microscopy and emission spectroscopy. 2. Quantity analysis of selected elements by means of atom absorption spectroscopy and emission spectroscopy. 3. X-ray phase analysis by means of a powder technique. The examinations have excluded the presence of heavy metals and elements with the atom number higher than „20” . The proportion of calcium and silicon, as found in the studies, has shaken the hypothesis on the use of glaze. On the other hand, it has allowed us to say that we have here a phenomenon of colour irrespective of the presence of the number of typical chromophores and that the two samples are a combination of at least two crystaline substances with a different size of grains, in this case of fluorite and calcite (the main component of whitewash). Thus, the element responsible for the colouring of the examined substance is fluorite, or to be precise its other form, namely antozonite. Fluorite from old excavations at Kletno was used as a comparative material. Deposits of this material are found in abundance in the Lower Silesia, Czechs, Germany, Bulgaria and Spain. The origin of the colouring has not been fully explained. It is assumed to be the result of the presence of free fluor, released from fluorite structures due to the effect of radioactive elements and is the outcome of net defects. The results of the studies made have enabled us to state that there exists a natural violet pigment and that it was certainly used intentionally in mural Gothic paintings in the Silesia. The authors of this report have given it the name of "the Silesian violet” .

Refine search results

1 Ochrona Zabytków

1 Wisła E.

1 Żurkowska-Mastalerz T.

1 1987

Search results

Fiolet "śląski" : identyfikacja nie znanego pigmentu w gotyckim malarstwie ściennym na podstawie materiału uzyskanego w czasie prac konserwatorskich w latach 1978-1985