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Four different calcitic marble varieties were analysed using acoustic emission (Figure 2).

Figure 2: Macroscopic and microscopic image of all analysed marble varieties. Top left depicts the Blanco Macael, top right the Großkunzendorfer, bottom left, Lasa and bottom right the Gioia.

The white spanish Blanco Macael (BM) shows a granoblastic grain fabric, with almost polygonal grain to grain contacts and a median grain size of 395 µm. The greyish Polish Großkunzendorfer (GK) shows a seriate to interlobate grain fabric, interlocking grain boundaries and a median grain size of about 545 µm. An equigranular-interlobate grain fabric was analysed for both Italian marble varieties. The white Lasa marble (LA) has a higher 187median grain size of 419 µm compared to the fine-grained Carrara Gioia (GI, 284 µm), a whitish variety decorated with greyish streaks. Textural analyses showed that, with the exception of the Lasa, all varieties have charateristics of a c-axis fibre type, with a single c-axis maximum for their lattice preferred orientation. They show moderate to slightly higher intensities between 1.6 mrd (multiple of random distribution) for the Großkunzendorfer and 2.9 mrd for the Blanco Macael. The Lasa marble shows a girdle-like c-axes distribution, surrounding the a-axis maxima.