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Material Sheet

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Pietra di Santa Brigida

stones
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other commercial names

Macigno di monte Senario

colour

Grey-blueish-tawny

petrografic name
(according EN 12407)

Litharenite

place of origin

Pontassieve (FI)

macroscopic description

A light grey, medium-grained sedimentary lithotype that is porous with slight black and mother of pearl speckling. Its appearance is homogeneous and compact.
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STANDARD U.M. MEAN VALUE ST. DEV.
EN 13755-08 Water absorption at atmospheric pressure % 1,52 0,09
EN 1936-07 Apparent Density KG/m3 2610 5,5
EN 1936-07 Open porosity % 3,78 0,36
EN 12372-07 Flexural strength
  (in natural conditions) MPa 15,2 0,9
  (EN 12371-03 exposed to 48 frost cycles MPa 13,7 0,4
EN 1926-07 Uniaxial compressive strength MPa 103 14,9
EN 14231-04 Slip resistance (honed finishing)
  (dry) USRV 70 5
  (wet) USRV 58 8
Average size of blocks: 3,00 x 1,50 x 1,50 m Slabs are sawn without any preference in terms of the orientation of the cut, at a minimum thickness of 10 m

Cutting of blocks Cutting of blocks   Surface finishing Surface finishing
A sandstone of a heterogenous, compact appearance with medium-coarse grain (0,1÷1÷5mm). In terms of size it is medium selected, with an anisotropic texture due to the tendency of isoorientation of the more elongated granules and subangular granules that are subrounded in the suborder. The clast fraction that shows compositional maturity has abundant siliceous holocrystalline lithoclasts (55%) of different types, although mostly schistose ones with chlorite and quartz; monocrystalline quartz (35%); feldspars (10%), such as microcline k-feldspar that is generally sound and albitic twinned plagioclases that are often deformed and in the alteration stage. There are fragments of basin intraclasts and bioclasts of opaque minerals mainly as widespread granulation. Abundant micas appear in traces – generally deformed – composed of muscovite and, in the suborder, biotite and chlorite, glauconite and garnets. The groundmass is scarce (< 5%, submature stage) and the cement is mixed, clayey/fillosilicate and in places calcitic.