Assayers Kellogg & Co.

The finest known 1855 proof Kellogg $50 gold coin, graded PCGS PR-64 Cameo CAC, sold for a record $1 million by Witter Coin in San Francisco and will be exhibited by its new owner at the store’s grand opening starting Feb. 10, 2020. (Image courtesy Professional Coin Grading Service, www.PCGS.com)
World Coin Auctions

'King of Pioneer Gold' 1855 Proof Kellogg $50 Sold for Record $1 Million