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John A. Grenzig

John August Grenzig, Jr. was born in Berlin, Germany on June 30, 1863, the son of John August Grenzig, Sr. In 1870, at the age of seven, he accompanied his parents to America and settled in Brooklyn. He began collecting minerals at the age of nine or ten. After leaving school he worked for a printing copany for several years, then sold flowers for a while. With the money he saved he went into the milk business, which he built up to an operation of six milk wagons. He then purchased a butter business and in the process was swindled out of everything. He next opened a dairy store, but that eventually had to be close because of diphtheria in the family. In 1899 he opened a grocery store in Woodhaven, which operated for eight years before he was forced to close.

In 1908, at the age of 45, he entered Cooper Union and graduated as an assayor. Upon graduation, he was offered a position as assayor for a mining company in Mexico, but because of the failing health of his mother he declined the job in order to remain in Brooklyn. He started an electrical contracting business in 1909, with his office and shop located at 299 Adams Street in Brooklyn.

Always wanting to show off his mineral collection to friends and customers, he eventually installed much of it in his contracting office, and thereby began a side-business in minerals almost accidentally. In 1894 he made an arrangement with the prominent mineral dealer Arthur N. Fuller (q.v.) in Lawrence, Kansas to display a selection of his mineral stock for sale at his office at 25 Starr Street in Brooklyn, and advertised this fact for two years in The Mineral Collector. Thus he became a serious mineral dealer himself, at times overshadowing his supposed principal profession, and eventually he moved his mineral business to new quarters at 299 Adams Street in Brooklyn. He developed numerous sources for specimens, and even bought whole collections on occasion. One tantalizing announcement in April 1934 reads:

"I have just taken over the well-known mineral collection of the late Louis Blumenthal which will be sold at my place of business. This collection is rich in the early minerals of Globe, Bisbee, Clifton, Yuma and Monmouth [=Mammoth?], all of Arizona, as well as [minerals] of New Mexico, Nevada, Colorado and part of California. This collection has not been unpacked since 1902."

The following year he took over the "extensive stock of Western minerals owned by Arthur Montgomery." Grenzig also built a personal collection of over 1200 rare and high-quality mineral specimens. He offered them for sale as a lot for $2500 in September 1941, but received no takers. He finally sold the collection on December 19, 1942, to his five best customers, in a kind of round-robin sale. He then offered his personal custom-built sold black walnut drawer cabinet for sale in June 1943. It was 56 inches tall, 50 inches wide and 26 inches deep with 20 drawers in two columns. He was also a micromounter, and by the time of his death he had around 1,500 mounts which were all outstanding for beauty and quality. He had a wide circle of friends and contacts throughout the country, and was well-liked by everyone who knew him. He died April 8, 1944.

Grenzig apparently did not have custom-printed labels of his own, preferring instead to provide simple typed labels like those shown here, probably also with the label of the original supplier (such as A.N. Fuller). Most of the labels shown here are among those accompanying a surviving collection of about 175 of Grenzig's specimens stored in five 2 x 2-foot drawers of an old wind-up phonograph (scans courtesy of John Grenzig's great-grandson, Ed Grenzig).

ZODAC, P. (1944) John August Grenzig: June 30, 1863 -- April 8, 1944. Rocks & Minerals, 19 (5), 142-143.
MAYNARD, Mr. (1944) John A. Grenzig. Rocks & Minerals, 19 (6), 183.
CONKLIN, L. (1995) Mineral stories: The Grenzig sale. Mineralogical Record, 26, 507.
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[Citation format for this entry:
WILSON, Wendell E. (2019)
Mineralogical Record
Biographical Archive, at]
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The Mineralogical Record - John A. Grenzig John A. Grenzig
The Mineralogical Record - John A. Grenzig John Grenzig ad from the April 1894 issue of The Mineral Collector.
The Mineralogical Record - John A. Grenzig 38 x 60 mm
The Mineralogical Record - John A. Grenzig 46 x 62 mm
The Mineralogical Record - John A. Grenzig 46 X 44 mm,
Dated July 4, 1937
The Mineralogical Record - John A. Grenzig 36 x 41 mm
The Mineralogical Record - John A. Grenzig 29 x 43 mm
The Mineralogical Record - John A. Grenzig 38 x 47 mm,
A label in Grenzig's handwriting.
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