A-Mark Precious Metals (AMRK) said Monday it agreed to acquire AMS Holding and completed the acquisitions of Spectrum Group International and Pinehurst Coin Exchange as part of its expansion into the collectible coin market.

The precious metals trading company said it agreed to acquire the remaining 90% of AMS that it didn't already own for $50 million in cash, with up to $12 million in additional payments based on performance. The deal is expected to close within 45 days.

A-Mark said it paid $92 million for Spectrum Group, the parent of Stack's Bowers Galleries, consisting of $46 million in cash and $46 million in stock priced at $27.51 per share.

The company paid $6.5 million in cash for the remaining 51% of Pinehurst and may pay up to $5.3 million more based on performance, A-Mark added.

The acquisitions are expected to increase A-Mark's customer base and gross margins during periods of low bullion volatility, the company said.

Shares of A-Mark were up 1.3% in recent trading.

Price: 28.03, Change: +0.36, Percent Change: +1.30