John Marshall found his first agate, a Lake Superior Agate, while doing yard work with his father at the age of seven in Mendota Heights, Minnesota. That find sparked an unbroken love affair with agates and lapidary. Soon after finding his first agate, John met William Bingham, discoverer of Binghamite, who was his primary mentor in lapidary and agate collecting. Later, he met Ray Lulling, discoverer of Silkstone, as well as other notable collectors of the time. John’s signature “curved face plate glass finish” on agates is known in the Lake Superior Agate region and worldwide.
Almost immediately, John became interested in the “other” non-banded agates, sometimes called “inclusion” agates. His first publication about agate formation appeared in the Lapidary Journal in 1965 when he was fifteen years of age. Much later in life, John published his book “The Other Lake Superior Agates’ in three editions in 2003, 2006, and 2009 with a new and enlarged edition, planned for publication in 2016.
John was the first, in collaboration with Scott Wolter, to notice the unusual “mosaic agate” present in some water-level agate specimens. John’s book includes a detailed hypothesis regarding the formation of mosaic agate structures. John also has made contributions in the description and explanation of unusual varieties such as the Lake Superior “skip-n-atom” agates and other highly unusual structures found within Lake Superior and other agates.
John was honored to have been included in the collector profiles in the book “Agates III” by Johann Zenz. That profile mentioned John’s pioneering role in development of international groups on social media devoted to agates. He founded “Agate Collectors Worldwide” on Facebook which at this writing has almost 16,000 members from around the world. This group has dramatically facilitated the sharing and understanding of agates across cultures and nations and will continue to do so in the future thus promoting agate collecting worldwide.
“Agates Collector’s Worldwide” Facebook Page: www.facebook.com/groups/Agatecollectorsworldwide/