Thursday, March 23, 2017

A Point With Multiple Dimensions


I manage to confine my collecting to a few, discrete interests, though the temptation is always there to add another.  I admit I felt a tug as I read novelist Gary Shteyngart’s account of his obsession with expensive, mechanical wristwatches, sparked by Donald Trump’s rise to power over the course of 2016.  Yes, it seemed to him that the time is out of joint.

How almost irresistible when he writes lovingly about his four-thousand-dollar Nomos Minimatik Champagner watch with its “exhibition-case back” revealing its inner mechanics:
[It] is a riot of sunburst decoration, tempered blue screws, and a small constellation of rubies.  A tiny golden balance wheel spins back and forth, regulating the time . . . , and this action gives the watch the appearance of being alive.  It is not uncommon for some watch enthusiasts to call this part of the watch its “heart,” or even its “soul.”  (Shteyngart, 2017, p. 38.  Full citations to all reference are provided in the Sources section at the end of this post.)
But, no, collecting mechanical watches would be far too expensive and possibly smack of affectation.  Even the few interests I’m feeding are too many.

Nevertheless, there is a virtue to multiple interests because, at some rare moments, my interests intersect, suggesting there may be some sort of logic to my collecting mania, not simply a psychological need.  So it is with a recent purchase, a rather small Native American projectile point with a broken tip from New York.  Though certainly not of high quality nor expensive, this point is profoundly appealing because in it are met three of my collecting passions – points, minerals, and fossils.
This is a triangular Madison Point, an identification based on William A. Ritchie’s A Typology and Nomenclature for New York Projectile Points (1961, p. 33-34), which squares with what the seller asserted.  According to Noel D. Justice, Madison Points were part of many “cultural phases across eastern North America” during the Late Woodland period, probably dating from 800 to perhaps as late as 1350 CE (Justice, 1987, p. 224, 227).  Ritchie describes Madison Points as “very finely chipped by pressure flaking” (p. 34), though I assume that the artisan who fashioned this point used some direct percussion flaking initially to shape it.  Ritchie also notes, “Among the northern Iroquois the principal material employed was Onondaga flint from the exposures of central New York and the Ontario Peninsula.”  (p. 34)  Absent any provenience (beyond the geographic state in which it was recovered), I won’t make any such claims for this particular point.

Nevertheless, my point is manufactured from Onondaga chert.  This gray chert is often referred to as flint, though, as I have learned, geologists apply the term chert to all of those rocks that artifact and rock collectors tag with such terms as flint or jasper based on differences in color.  As Prothero and Lavin write, “The color differences are not only superficial, but frequently misleading, especially since heat treatment may change the color range of a particular chert.”  (Prothero and Lavin, 1990, p. 561.)

Chert has a geological life story understood in general, but apparently not in its smallest details.  It is a hard sedimentary rock composed of silica (silicon dioxide) in the form of very tiny crystals, either only discernable under a microscope (microcrystalline) or not even then (cryptocrystalline).  This material comes into being through what has been characterized as “an obscure chemical process”  (Roberts, 1996, p. 24) involving the precipitation of silica from solution.  Chert can be found as nodules, lenses, or beds depending upon the environment within which it forms.  Given its fine crystalline composition, chert fractures conchoidally, that is, “fracture faces have smooth, curved surfaces” with sharp edges (Ostrom and Peters, 2012, p. 12) which makes it ideal for fashioning projectile points, scrappers, and knives.

Assuming the chert in this point was found as a nodule, which is likely given its origin in the Onondaga Formation dating from the Devonian Period, it is also highly likely that the source of its silica was the hard silicon elements (spicules) that sponges secrete to give themselves structure and a means of protection.  (Maliva et al., 1989, p. 523)

From their analysis of thin slices of the chert from different sites in the northeastern U.S., Prothero and Lavin find that the chert in Native American implements can often be easily identified as to its place of origin.  I found their description of chert from western New York State particularly applicable.  They write, in part, of this chert:  “Small (0.1 mm in diameter) dolomite rhombs are abundant, but there are few large rhombs.  Fossils and pyrite are common . . . .”  (Prothero and Lavin, p. 570)

Two elements of that description ring very true for the point I have in hand.  First, there are the dolomite rhombs which are the rhomboidal crystals or impressions of those crystals left by some dolomite caught up in the geological process creating the chert.  The mineral dolomite is a calcium magnesium carbonate and is the primary component of dolomite, a biogenetic sedimentary rock.  Pictured below is a close-up (30x) of a small portion of one face of my point.  This chert, under magnification, appears less strongly colored than a more removed view would have it since the color is, I surmise, often the cumulative effect of impurities in the mineral.  I have marked several of the rhomboidal shapes that appear on the surface of this section of the point; these are, I assume, dolomite rhombs.


Then there are the fossils in Onondaga chert which is where another of my collecting interests finds play in this point.  Pictured below is the full point (minus, of course, its tip) with an inset showing a closer look at a small hole in its surface – a fossil mold.
Given the common occurrence of fossils in Onondaga chert, it isn’t at all that surprising that Native American stone artifacts fashioned from this material would, sometimes, contain a fossil or two.  Source of the mold in my point?  The seller suggested coral and he may well be right.  But, the impression in the point strongly reminds me of columnals from some types of crinoids.  These animals, also known as sea lilies, create long structures of “stems” topped with long branch-like appendages for food gathering.  Secreted calcium carbonate pieces (ossicles) provide crinoids with structure and protection; in the stem, the stacked individual ossicles are known as columnals.  Crinoids are still with us, but their fossil record goes back well before the Devonian Period, which means that, yes, they were around when and (based on my reading) where the Onondaga Formation was laid down.

Pictured below is a bit of a Devonian crinoid fossil (first image) I found at a site in Maryland exposing Needmore Shale (which has been stratigraphically correlated to the Onondaga Formation in the Devonian’s Eifelian Age, about 393 – 388 million years ago).  The arrow points to where some columnals remain (the grooves to the left of the head of the arrow are where columnals have been lost).  The columnal in the second image, the first one remaining in the stem, appears to match nicely the mold left in my point.



Sure, not conclusive evidence, but wonderfully suggestive.

Shteyngart’s New Yorker essay is, ultimately, quite dark.  As the presidential campaign unfolds in 2016, his need to buy watches spirals out of control; he is “in deep.”  I may be contorting his message, but when he writes of how people cope and coped in Putin-era and Soviet-era Russia (e.g., collecting deluxe shaving equipment or compulsively doing mental math problems), I read him as saying that, in a society out of joint, we turn to find refuge and security in “the particular and microscopic” because they are “the only things that could still prove reliable.”

He may have a point.


Sources

Noel D. Justice, Stone Age Spear and Arrow Points of the Midcontinental and Eastern United States, 1987.

Robert G. Maliva et al., Secular Changes in Chert Distribution:  A Reflection of Evolving Biological Participation in the Silica Cycle, PALAIOS, Volume 4, Number 6, December 1989.

Meredith E. Ostrom and Roger M. Peters, Wisconsin Rocks and Minerals, Wisconsin Geological and Natural History Survey, ES046, 2012.

Donald R. Prothero and Lucianne Lavin, Chert Petrography and Its Potential as an Analytical Tool in Archaeology, in N.P. Lasca and J. Donahue, editors, Archaeological Geology of North America, Geological Society of America, Centennial Special Volume 4, 1990.

William A. Ritchie, A Typology and Nomenclature for New York Projectile Points, New York State Museum and Science Service, Bulletin Number 384, April 1961.

David C. Roberts, A Field Guide to Geology:  Eastern North America, 1996.

Gary Shteyngart, Time Out:  Confessions of a Watch Geek, The New Yorker, March 20, 2017.

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