They have beautiful colours, unusual shapes and sparkle in the sun like diamonds. The mountains of Val di Fassa hide a mine of minerals and fossils. It was the hunt for minerals in the volcanic areas of the Dolomites by Tone Rizzi Poldin that lead to the birth of the Monzoni Mineralogic Museum that offers the possibility to admire quartz, agate, monzonite, analcite of various colours, fassaites, cornelian and many more. The exhibition is in a spectacular renovated hay barn. The museum is found in Strada de Pilat in San Giovanni di Fassa and is open in summer, from end of June to beginning September, every day.