Very cool, Joe. Although yours is most probably a modern replica, especially if magnetic. To find out if it is some type of trial piece, a professional authenticator is required. Compare your coin carefully with our images.
Genuine commems come in silver and gold. The gold one pictured above sold for $6000 US dollars, the silver for $1700. CoinQuest thanks Gorny & Mosch and Lanz for use of their amazing coin photos.
Auction Lanz (gold):
Price realized: 6,000 USD
CZECHOSLOV AKIA Commemorative 10 Ducats 1934 K, Kremnitz, referring to the reopening of the mines of Kremnitz. + S . CIVITATIS . REGIS CAROL . DE . CREMNICIA *, praying haloed Catherine right in flower shaped frame, circumscription in hexagonal frame. Rv: Circumscription in beaded circle at both sides, in hexagonal border mining scenes depicting above- and underground work, fineness punch and signature A. HAM (Anton Hám) to the right. Fr. 13, Müseler 9/6. 34,93g. 41mm. Only 68 pieces were struck. Almost uncirculated, proof. Estimate: 8000 USD
Gorny & Mosch, via Google translate (silver)
TSCHECHOSL OWAKEI First Republic, 1918 - 1938/39. Medal 1934 in the style of the multiple ducats of the year. Mzst. Kremnitz, Mts. A. HAM. To celebrate the reopening of Kremlin Mining. Kneeling to pray, St. Elizabeth, + S CIVITATIS REGIS CAROLI DE CREMNICIA. / Mine plant on average, miners at work. OZIVENIE KREMNICKENO BANICTVA 1934, small blazon with the bohemian lion. On the left side of the shield a hallmark '987', on the right a hallmark with 'K' on hatched ground. 30 mm. 9.94 g. Müseler cf. 69/6 a var. R! Fine patina, almost St Estimate: 250 EUR