Predazzo and Monti Monzoni areas.  Around the village of Predazzo and in the Monti Monzoni group there are different kind of igneous volcanic and plutonic rocks, together with metamorphic formations in the contact areas

Gehlenite
White pseudocubic XX on matrix, max edge 0.8cm
8x8cm
Monti Monzoni, Selle Lake area, Val di Fassa, Trento. Italy
Specimen n.368

Kaersutite
Typical black X, 1cm tall, in the volcanic rock. Undamaged XX are not so common
6x4.5cm 
Bersaglio, Predazzo, Trento. Italy
Specimen n.228

Other areas

Calcite
Clear yellow X, 2.8x3.3cm, with other yellow and white semitransparent smaller XX, on matrix of limestone. In 2002 beautiful pieces were extracted, from cavities in  a dolomitic rock; the XX are originated by carbonatic deposits due to hydrotermal actions
8x7.5cm 
Mezzolombardo, Trento. Italy
Specimen n.212

Another photo: a different view

Calcite
Another XX from Mezzolombardo; it is white and 2x2.7 cm wide, posted on a matrix covered by other small calcite XX
8x9cm 
Mezzolombardo, Trento. Italy
Specimen n.933

Another photo: a bigger view

Calcite
Semitransparent scalenohedrons up to 3cm long, from a nearly unknown locality
6x4.5cm 
Imer, Valle del Primero, Trento. Italy
Specimen n.818

Orthoclase
Orthoclase immersed in the volcanic rock
5.5x4.5cm 
Val Floriana, Trento. Italy
Specimen n.850