Very little is recorded of Charles Pletz beyond a few bare notices in Arizona's Weekly Miner newspaper of the mid-1870s. The paper's issue of May 14, 1875 notes Pletz as superintendent of the Mass Mine while the following June 4 the paper notes Pletz' interest in mining in the Mineral Park District. For July 9, 1875 the paper stated that Pletz would operate a mining mill at Mineral Park. The issue of October 22, 1875 noted that Pletz had opened an assay office, location not noted. On July 14, 1876 the paper reported that Pletz was to be named supervisor of the Quartz Mounting Mill. On November 17, 1876 the same paper noted Pletz as assistant assayer of the Aztlan Mill and on March 9 of the following year reported that Pletz had sold an interest in the Everett Mine. The last mention of Pletz is a notice in The Miner of November 9, 1932, that describes a place in the Cerbat Mountain where a certain Jack Flynn dug out several hundred pounds of silver ore, samples of which assayed out at Pletz' assay office at more than $3,000 a ton.

There are only three known Pletz ingots. The ingot from the John J. Ford, Jr. Sale was no. 141. Ingot no. 235 was illustrated in How They Dug the Gold (Arizona Pioneer's Historical Society, 1967). Mr. Ford contacted the bar's owner, a Mr. Milton Singer of Bloomfield, Connecticut in August, 1973, asking, without success as it turned out, if the bar were for sale. In his letter to Singer, Mr. Ford mentioned he knew of one other Pletz ingot, bar no. 141. Nearly five years later, on February 20, 1978, Mr. Ford made a second attempt to buy Singer's Pletz ingot, this time offering $1,000 for it. Mr. Singer again declined to sell the bar, but sent Mr. Ford photographs of it for his files.

Then, on December 17, 1979 Don Kagin received a letter from Mr. Singer asking if there was a Pletz bar in the Clifford Collection. Don forwarded Singer's letter to Mr. Ford, who replied that there wasn't and reminded Singer once again of Ford's interest in buying Singer's Pletz bar. Singer graciously declined once more, but offered Mr. Ford some information that helped locate Pletz' assay office in Mohave County, Arizona. In December, 1984, Singer wrote Ford saying that his son wanted to have the Pletz bar, implying that it was thereafter off the market, but the bar appeared for sale in John Hamilton's fixed price list offering published in the TAMS Journal in February, 1991. In February, 1993 Hal Birt wrote Ford saying that Hamilton had brought the bar to the recent Tucson show. Its present whereabouts are unknown to the cataloguer and were to Mr. Ford.