February 1, 2022, Monthly Meeting

On Tuesday, February 1, 2022, at 7:00 p.m., we’ll be having our monthly meeting virtually, featuring…

Pseudomorphs, Trickster Mineral Specimens

with Howard Heitner!

Members, watch your email for connection information!

The details…

Howard’s talk is on “Pseudomorphs, Trickster Mineral Specimens.” The word pseudomorph was first used by Hauy in 1801. The term comes from the Greek, meaning “false shape.” A pseudomorph is a mineral that has the external crystal shape of another mineral. Pseudomorphs were first written about in detail in the 19th century by German mineralogist Johann Blum and were more recently systematized by the mineralogist Strunz in 1982. This talk covers various theories of how pseudomorphs form. In cases where a second mineral of similar composition replaces an original mineral, the mechanism is usually a chemical reaction. In cases where the two minerals are not chemically related, the mechanism of pseudomorph formation can be more complicated. There is still controversy about the formation of some types of pseudomorphs. Howard’s talk will be illustrated with pictures of both common and rare pseudomorphs.

About the presenter…

The speaker for our February meeting is Howard Heitner. Howard has been a mineral collector for over 60 years, starting with field collecting in New York, New Jersey, and Maine. He subsequently began purchasing specimens, including several old collections, which triggered an interest in the history of mineral collecting and mineral dealing in the United States, as well as in fluorescent minerals and pseudomorphs. For several years, he was president of the Stamford Mineralogical Society. In his professional career, he was a polymer chemist working on specialty chemicals for the processing of minerals. He has spent his retirement organizing and cataloguing his collection and presenting on mineral-related subjects. He worked as a docent at the American Museum of Natural History and is currently a volunteer at the Rochester Museum and Science Center in Rochester, NY.