The pseudometeorite Angara

Authors


E-mail: holger@nbi.ku.dk

Abstract

Several pallasites are known to have formed strewn fields with multiple fragments. Therefore, it seems possible that the famous Krasnojarsk pallasite—the Pallas Iron of 687 kg—could have been accompanied by one or more additional fragments that had not been recovered due to incomplete observations from the overgrown and remote place of fall. During a survey for literature accounts of distant fragments in such a hypothetical strewn field, a report of native iron was found, dating to 1847. The fragments of nickel-free iron—amounting to at least a few kg—had been recovered 1836–1843 during placer gold mining north of the Angara River. The position of these finds is coincident with Burovaya, Murozhna, and Uderei, the three known fragments of the pseudometeorite Angara, all collected in 1885.

Introduction

It is well known that several pallasites (e.g., Admire, Albin, Brahin, Brenham, Huckitta, Imilac, Seymchan) were recovered from strewn fields with two or more fragments. As the typical mass of these meteorites is within an order of magnitude from that of the Pallas Iron, it appears plausible that also this latter object could have been part of a strewn field, which because of its location deep inside a Siberian forest remains poorly surveyed.

There are indeed some (unconfirmed) hints that fragments of the Krasnojarsk meteorite were collected subsequent to the discovery of the Pallas Iron, in 1749 (or 1752, see below). In Paul Partsch's description of meteorites in the Imperial-Royal Mineral Cabinet in Vienna (Partsch 1843), a communication from the London-based mineral dealer Henry Heuland is cited, to the effect that an associate of his, Sitnikoff, had purchased more than two hundred pounds (90 kg) of Krasnojarsk fragments as old iron at a flea-market in Moscow, in 1807, and it is hinted—by Partsch—that this mass had a separate origin from the Pallas Iron. Partsch presumed that the material was collected subsequent to the Pallas Iron and he expressed regret that the opportunity to follow up on the matter had been missed. This account has been cited by Anonymous (1845), August (1850), Clark (1852), Forchhammer (1855), Quenstedt (1872), and Muller (1876). The curator of meteorites in St. Petersburg, Adolf von Goebel (1867), concluded that the amount was exaggerated, but he did not put the sale into doubt.

Beginning 1806 and in company with Heuland, Sitrikoff (presumably the merchant Luca Timofeevich Sitrikoff) held a virtual monopoly on the sale of Siberian minerals to collectors all over Europe; a nephew of his traveled through Siberia in 1807, in search of minerals (Cooper 2006). Cooper described Sitrikoff as suffering from “mendacity”; contemporary documents use terms as “a most wicked man,” and “an extorsioner.” It can safely be concluded that he was not of curatorial or scientific attitude. What truly is behind the alleged flea-market sale will therefore remain obscured in the mist of history. It begs the question how the new material can have been associated with the Pallas Iron, unless found in close proximity.

The fact is that Heuland was able, during many years, to keep trading Krasnojarsk fragments to collectors and nobility, and it is tempting to speculate that their origin was in the flea-market material, and not, as often believed, in the Pallas Iron.

Independent of Partsch's account, the curator of meteorites in Stockholm, A. E. Nordenskjöld (1871), mentioned that “countless” pieces of the Krasnojarsk meteorite in (private) Swedish collections “seem, at some time, to have arrived directly from the Ural.”

If indeed a multitude of minor masses have been collected at a separate location from the Pallas Iron, they may well be due to impact scattering of a large fragment—much like the Chilean pallasite Imilac, which underwent two fragmentations—one in the atmosphere, and the other on ground impact of the largest fragment (see Pedersen and Garcia 1987). Fragments that have their origin in the impact event will in general not show marks from human separation, e.g., from hammer, chisel, or hack-saw, nor would a large fraction hold fusion-crust. Pieces detached by Peter Simon Pallas and by the Imperial Academy of Science—until the traffic was stopped in 1786 (Wendland 1992)—should in general show evidence for forceful handling, and many will be exterior pieces, with remnants of crust. It should here be recalled that teams of three to four smiths had great trouble, using chisels/axes and hammers, when trying to dislodge samples of a couple of pounds mass (Pallas 1776; Patrin 1802; Wendland 1984).

In a letter dated July 18, 1777, and sent to the Gesellschaft Naturforschende Freunde Berlin (transcribed by Wendland 1984), Pallas distinguished between fragments separated by means of hammer and chisel, and those initially sent from Krasnojarsk, in 1773. Taken literally, this must mean that the early fragments were loose pieces. In the same letter, Pallas refers to an order sent on his behalf by the Mining School at St. Petersburg to Irbinskoi Sawod (a smelter on an up-river tributary to the Jenissei, where Johann Caspar Mettich, one of the finders of the Pallas Iron, was site-manager, cf. Eremeeva 1982, p. 39), requesting a careful search for more masses on the mountain, where the big mass had been found. It would thus seem that Peter Simon Pallas was aware that further fragments either had been found in nature, or could potentially be found.

The role of the 150-fathom (approximately 280 m) distant, 70%-rich, magnetic iron ore (cf. Pallas 1776) should, perhaps, be reconsidered. While a number of authors have proposed a common terrestrial origin of this mineral outcrop, and the Pallas Iron (e.g., Patrin 1802; De Chancourtois 1872), perhaps both were meteoritic. From elsewhere, e.g., Vaca Muerta, it is known that a surface-exposed, weathered meteorite may lead to considerable mining activity, including the use of drilling and gun-powder blasting (Pedersen 2012). The cited distance, 150 fathoms, may indeed be in error for “less than 100 fathoms,” which was the value initially given by Pallas (refer an article printed in Sankt Petersburger Zeitung on September 6, 1773 and reprinted in part in Stockholms Post-Tidningar, on October 14, 1773, and by De Stehlin 1774). During Innokentii Lopatin (1839–1909) and Alina Eremeeva's attempts in 1873 and 1978–1980, respectively, to rediscover the finding-place of the Pallas Iron, minor amounts of magnetite were found in the hills, but far from the concentrations cited originally (cf. Goebel 1875; Eremeeva 1980). It should be recalled that exploitation of this mine ended the year it began, 1752 (Pallas 1773), this year being the first one cited for the initial discovery, rather than 1749, as stated from 1776 onward.

To investigate if Partsch, Nordenskjöld, and to some extent Pallas could be right, the author has conducted a survey for mention of possible distant outliers in a potential strewn field for Krasnojarsk. Two candidate accounts were found. A 66.5 g pallasite fragment in Jena, which in Frits Heide's handwriting carries the label “Beresowsk, Ural,” is, according to Franke and Bruckner (1977), to be associated with Krasnojarsk, the name stemming from either of two locations, “Beresowskoje” some 200 km west of Krasnojarsk, or “Beresowska,” 20 km east. None of these locations appears to be on a likely trade route away from the Pallas Iron finding place.

William Sullivan's Report on Native Iron

A second, literary, account that associates the Krasnojarsk pallasite with the find of small pieces of native iron in the region of Krasnojarsk can be read in a paper on the interplay between nature and indigenous languages and mythologies, published by the Irish linguist William K. Sullivan (1859).

I have specially mentioned this mass [the Pallas], because I have read somewhere, but cannot now recollect where, that in the regions about the upper Tunguska [i.e., Angara river], small masses of native iron are very common, and that many of these have been employed by the natives. Ernest Hofmann (1847) has recently mentioned having received from Mr. Nicolai Maesnikow, of Krasnojarsk, a small sample of native iron, which had been sent to him as platinum from some of the surrounding districts, but the name of which was not communicated. It consisted of splinters, which had the appearance as if cut with a sharp instrument from some iron utensils. They were obtained, it was said, instead of gold, in an alluvial deposit, by a party sent in search of that metal by Mr. Maesnikow. It is very probable, as Hoffmann suggests, that there had been deception or mistake about this extremely unusual deposit. It is singular, however, that such a story should arise in the district in question, and obviously, there must have been some circumstance to suggest even such a deception.

Ernst Hofmann (1801–1871)

The work cited by Sullivan is based on the Dorpat (Tartu)-born geologist Ernst Karl Hofmann's inspection travel to the East Siberian gold-washes in 1843. His book had first appeared in a Russian translation, but in the foreword to the presently cited version, he assures that it is based on the original, German manuscript.

During the years 1823–1826, Hofmann had sailed around the world on the sloop “Betrieb” (Enterprise), being encharged with geological observations. While calling at Hawai'i, he was alerted to the Owahu meteorite (Partsch 1843). Before the mission to Siberia, Hofmann was a lecturer in Kiev, subsequently in St. Petersburg. His extensive travels in the Ural mountains resulted in the first systematic description of that region's geology. Of his huge, private collection of minerals, more than 1000 specimens remain in the Mineralogical Museum of St. Petersburg University.

The alluvial gold mining of eastern Siberia that was the topic of Hofmann's travel in 1843 had begun in 1836. It was being conducted by great vigor, summer-time only, to a large extent using migrant workers, exilées, and former prisoners. Some of the largest operations were North of the Angara River, around the tributaries Murozhna and Uderei; the plants were organized out of Krasnojarsk.

Hofmann's Report On Native Iron

Three text segments on p. 75, 77, and 195–196, respectively, mention the find of native iron.

Page 75: On the fifth day we arrived to the [rivulet] Peskin and were greeted by Mr. Nicolai Maesnikov himself, at his wash Inokentiewsk on the large Peskin…. Small bits of jagged, native iron are frequently found at the wash Uspensk, and only there. From the way they appear, they are broken parts of implements made out of cast iron, and this opinion is strengthened by all exterior signs; however, at the wash, only tools made out of wrought iron are used, and therefore the presence of these splinters remains a mystery to me.

Page 77: From Mr. Nicolai Maesnikov, I received a small sample of native iron that had been sent to him from a location that was not named. They are small splinters that fully have the look, as were they chopped off with a sharp instrument from some tool of iron; they are thin, somewhat bent, with a corroded or rusty surface and contains only iron, and no trace of nickel, for which they were examined. With it, I received the following message regarding their occurrence, which is so noteworthy that I shall not exclude that Mr. Masenikow not has been cheated by his staff, since in Siberia, the search-parties will often promote lies at free will. One search-party, sent out by Mr. Maesnikow to find new alluvial gold sand deposits, found an alluvial metal deposit (orig: Trummerlager), that instead of gold held this metal in question. The deposit was 40 Verts [1 Verst = 1.0668 km] long, and contained according to the tests made so far, 7–10 Solotnik [1 Solotnik = 4.265 gram] metal in 100 Pud [1 Pud = 16.38 kg] sand. The metal was taken for platinum, and a registration recommended, however when tests with a magnet showed them to consist of iron, the registration was called off. This notice would constitute an entirely uncommon presence of native iron, if it were so trustworthy, as Mr. Maesnikow was convinced that it is. My request to let wash a couple of pounds of this iron remains, until now, as far as I know, without result—which can, by the way, be explained, considering the large distance of the place from populated sites.

Page 195–196: The gold wash Uspensk, belonging to Mr. Ignati Resanow [is located] at the Besimänka, 1040.4 Parisian foot above Krasnojarsk…. The gold is mostly fine-grained; in the concentrate occurs, in addition to cubes of goethite [orig: Brauneisenwurfel], rather frequently also jagged pieces of native iron that have the appearance as were they broken off from large, porous masses.

The gold wash Inokentiewsk is marked on the map provided by Hofmann. Although the map suffers from distortion between the Uderei and the Murozhna river-systems, the site in question can easily be located on modern maps, at the position: 58°45′ N, 94°14′ E. Hofmann's travels also took him to Murozhna, but no find of native iron was reported from there.

The Angara Pseudometeorite of 1885

The first mention of a possible meteorite at Angara river, Siberia, can be found in Wülfing (1897), where it is listed in the Appendix, among “poorly documented meteorites and doubtful pseudometeorites.” The three bits of iron were found in 1885 during gold mining of river beds, specifically at Murozhna, Uderei, and Borovaya (for which various synonyms and transliterations are known). Following initial deposition in St. Petersburg, they are now at the Vernadsky Institute, Moscow. The concentrations of Ni, Co, and Cu were measured by Zavaritskii and Kvasha (1952), who also gave other particulars, and concluded that all three finds were not meteoritic. The Meteoritical Bulletin of 1959 (List No. 2) begs that Angara be removed from the catalog of Prior and Hey (1953).

Table 1 lists the positions derived by Hey (1966) and the element concentrations and ratios by Zavaritskii and Kvasha (1952).

Table 1. Fragments of the pseudometeorite Angara
 MassPositionNi (ppm)Co (ppm)Cu (ppm)Ni:Co:Cu
MurozhnaOne of 103.8 g58°41′ N, 94°14′ E    
UdereiOne of 15.2 g58°43′ N, 94°26′ E0.0330.031.41:1:3
BorovayaOne of 65.5 g58°41′ N, 94°14′ E0.370.351.01:1:3

As the numeric element concentrations do not match the ratios, we presume that there is a misprint, in the values for Ni and Co, for Uderei. This can best be verified by a renewed analysis.

The Murozhna/Borovaya-position is some 7 km South of Inokentiewsk.

Conclusions

An account has been located, postulating the find of pieces of native iron north of the Angara river. The total mass must have amounted to several kilograms. The verbal description is consistent with that of minor pallasite fragments, as seen in, e.g., Imilac, but because a test for nickel was negative, a meteoritic origin seems unlikely.

The location of these finds is consistent with the later finds of native iron near Burovaya, Murozhna, and Uderei. These have been found to have a low concentration of Ni, leading to a firm conclusion that they are not meteoritic. The approximately 450 km distance from the find location for the Pallas Iron is a strong further argument against any association to the Krasnojarsk pallasite.

Native iron is rare on Earth, and we are not aware of any finds similar to those described here.

Acknowledgments

It is a pleasure to thank Vagn F. Buchwald (Copenhagen) for a discussion on the merits of Hofmann's account, Lisbeth Dilling (NBI library) for obtaining a copy of Hofmann's map, Anna A. Plyashkevich (NEISRI FEB RAS, Magadan, Russia) for translation of the Russian work from 1845, Jorn Koblitz (MetBase) for mailing a copy of Zavaritskii and Kvasha's description, and Christian Koeberl (Vienna) for carefully reviewing earlier versions of the present text.

Editorial Handling

Dr. A. J. Timothy Jull

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