One of the less-prominent displays at the Tucson Mineral Show 2008, and not an official part of the "American Mineral Treasures" display was this curious cabinet of specimens that were originally from the collection of the American Philosophical Society. Dating back to the early to mid 19th century, these specimens, until recently, were housed with the mineral collections at the Philadelphia Academy of Sciences. They have now been kept together as a complete collection by Peter Megaw - thankfully instead of being sold of piece by piece.
Some of the specimens
Although not by any means spectacular display specimens in general, many of these pieces had a long and curious history, and here are some examples from that display.
Rock Salt (Halite) from Louisiana Territory
Rock Salt (Halite) from 'The head of the Arkansas, Louisiana Territory'
This sample of Rock Salt (halite) was recorded as "from a creek at the head of the Arkansas" (river) in Louisiana Territory. The modern label suggests that this sample may have been returned from the Lewis and Clark expedition (1803-1806). For those of you who are not knowledgable in the history of the US (and you have no excuse, there isn't much of it!), this was a famous expedition from the St Louis in the east to the pacific ocean and back, mapping out the land, peoples and and natural wonders found en route. A description from the journals of Lewis and Clark
[1] says:
Great Saline to the westward of the main branch of the Arkansaw. From the Osage Town on the Osage River 11 days travel to the Great saline. From St Louis to the Osage Village thence West 120 leagues to the great saline Situated on a Southern Branch of the river Arkansas called niscud [Ne-ne-scah] and by the French the River of the grand Saline which after pursuing a course of about 40 leagues discharges itself into the Arkansas around 30 leagues due West, from the great Saline and Situated on the S W Side of a considerable Southern branch of the Arkansas Islans [is] the Saline which Produces the Purest rock salt. it is of a white a clear colour, this Stream is called by the Osages the Na chu richin gar.
One thing made me curious about this story however, and that was the question mark at the end of the label. Was this specimen from the Lewis and Clark expedition? And here the story gets even more interesting. The American Philosophical Society were the recipients of a large number of items recovered from this expedition, so it's quite probable that this sample was from that trip. But there is another possible source. In 1803 the young United States purchased the Louisiana Territories from the French, but it seems that few people, even the President, had any real idea as to what was contained within the areas they were purchasing. President Jefferson talked about a 'Salt Mountain':
[2]
One extraordinary fact, relative to salt, must not be omitted. There exists, about one thousand miles up the Missouri, and not far from that river, a salt mountain.... This mountain is said to be one hundred and eighty miles long, and forty-five in width, composed of solid rock salt, without any trees, or even shrubs upon it. Salt springs are very numerous beneath the surface of this mountain, and they flow through the fissures and cavities of it.
Of course, a 'Salt Mountain' didn't exist. The rumour was probably started by Zebulon Pike in 1803, before the Lewis and Clark expedition, who spoke of a 'mountain of salt' in the west, after seeing 'bushels' of it in St. Louis. It wasn't until 1811 that someone tried to find this 'mountain', and that someone was George Champlin Sibley, who after exploring for this mountain reported back to his superior, William Clark (of Lewis and Clark fame) the following:
It is a level flat of redish colored sand containing about 500 acres longitudinally intersected by a small stream [the Buffalo] which flows into a branch [the Cimarron] of the Arkansas. It is bounded from S.E. to N.N.W. by very lofty hills, whose sides next the saline area are for the most part perpendicular and faced with rugged rocks of gypsum of various kinds intermixed with red clay and some flint. From the bases of these hills issue many springs of salt water. There are also four springs that arise within the flat. . . . The water of the springs in the flat is so strong that salt will not dissolve in it. After a long series of very hot weather this section is nearly all covered with a solid rock of salt from 5 to 12 inches thick, and immediately round the four springs, a kind of hollow cones of salt are formed more than two feet above the general surface; at one of these I hewed out with my tommahawk a block of salt 16 inches in thickness. . . . The quality of the rock salt is unquestionably superior to any that I ever saw. It is beautifully white. . . . herewith are some few specimens of this salt, and also some of gypsum.
So. Perhaps this sample is from the Lewis and Clark expedition, or perhaps it is from the Sibley expedition of 1811 (and how many specimens in YOUR collection have been collected with a tomahawk?) Either way, it's a fascinating specimen.
Rock Guano from Monk's Island
"Rock Guano" from Monk's Island
This is a curious specimen of a phosphate material (which when analysed proves to be mostly Apatite). The Proceedings of the Academy of Natural Sciences of Philadelphia published an article on this material in 1858, and there is every chance that this specimen was one of those examined for this.
[3]
The Guano rock is found on Islands NE and N of the coast of Venezuela in the Caribbean Sea and belonging to that Republic. The islands form groups or keys composed of one hundred or more small islands inhabited principally and indeed almost solely by water fowl who resort there in immense numbers for laying their eggs. Mr Cassin informs me that the birds are those commonly known as Gulls, Pelicans and Cormorants. These have been the instruments by which the immense deposits of Guano have been formed. But what the process has been is a problem not yet fully solved.
The Columbian Guano is a hard rock consisting of two distinct portions the outer exterior crust consisting of a white, frequently reniform, coating, which in places where it is not decomposed has a polished surface not unlike enamel. It is composed of concentric layers each of which is about two or more lines in thickness. The entire outer crust forms but a very small proportion of the whole rock. A carefully selected portion of this has been analyzed which had not undergone any apparent decomposition and upon which the enamelled surface was well preserved. In some portions the reniform surface is distinctly marked and it resembles to a certain extent in its appearance the
menilite from Menil Montant near Paris; the concentric layers composing it are well marked, and when they are fractured or cut across, an appearance is presented not unlike some varieties of agate.
This "Rock Guano" was categorized at the time within a group of phosphatic "minerals" called the "pyroguanites". The name, from the Greek for fire and the word guano, was originally coined because it was believed that the rock had been formed by the action of heat on guano deposits
[4], however it was clear by the time of this 1858 article from Philadelphia that the rock had been formed by the action of seawater on Guano.
Tourmaline from Orford, New Hampshire
Tourmaline from Orford, New Hampshire
A real crystalline mineral, for a change! This tourmaline (probably Dravite) in a talc-shist has a label that reads "Oxford, New Hampshire". Now, Oxford seems to be in Maine as far as I remember - but closer investigation shows the original label is 'Orford'. And yes, the Orford Soapstone Quarries were active between 1800 and 1835 and produced dravite in talc-shist
[5].
The modern-day label maker may be slightly relieved to know that he wasn't the first to make this mistake. While trying to track down the mythical "Oxford, NH", I came across a listing in the Annales des mines by France Commission des Annales des mines (1831) discussing tourmaline, and one of the specimens they list is:
No.4 T. brun noirâtre, d'Oxford (New-Hampshire) dans un schiste talqueux.
Aquamarine from Acworth, New Hampshire
Aquamarine from Acworth, New Hampshire
Unfortunately another mis-transcribed modern label, but this nice laump of crystalline Beryl from Acworth, New Hampshire was a very average specimen at the time
[6].
An enormous specimen is also described in Silliman's Journal as having been found at Acworth in New Нampshire, United States. Its dimensions are stated to four feet in length and five inches and a half acrocs the lateral planes and the weight to be 238lbs
Vesuvianite from Sanford, Maine
Vesuvianite from Sanford, Maine
I promise, I didn't deliberately choose specimens that had badly transcribed modern labels, but here is another one. Trying to find 'Sandford' obviously took me nowhere. This classic specimen is particularly interesting, as according to Mindat, the site is still open for collecting and Vesuvianite is being found there today. Have a look in the gallery for the locality and you'll see some nice pieces collected in recent years.
This is a classic "Dana Locality", and is described under the entry for Idocrase in his 'System of Mineralogy' (1835) edition:
fine green prisms from half to five inches long Sanford mine, East Moriah, Essex Co.
"Epson Salts" from Hayne's Cave, Virginia
Epson Salts (Magnesium Sulfate) from Hayne's Cave, Virginia
This vial of Epson Salts holds an interesting history. A small block of text accompanying the display explains the background:
In 1796, Thomas Jefferson was sent some bones from a cave in Geenbrier County, Virginia. Jefferson described these bones as a new genus of mammal, Megalonyx (a type of giant ground sloth). Jefferson reported the bones were found by saltpeter workers but was unclear about its precise location. Organ Cave was previously believed to be the location of this discovery but letters written by Tristram Patton, the next owner of the property, indicates it was really Haynes Cave in Monroe County. Patton described the cave and indicated more bones were found there. This vial of Epsom salts was given to William ___? by Patton in 1804 with the notation that they were extracted from Jefferson's Megalonyx site. This indicates Haynes Cave is correct.
What we don't know is whether the jar contains natural crystalline
Epsomite taken from the caves (if often forms as encrustations on walls) or whether this was purified and recrystallized.
Tourmaline from Chesterfield, Massachusetts
Tourmaline from Chesterfield, Massachusetts
Another nice specimen was this green (Elbaite?) Tourmaline from Chesterfield, a famous site for Tourmaline. A report in the American Journal of Science in 1818 describes this locality
[7]:
The red or rose tourmaline of Massachusetts is found chiefly at Chesterfield in a subordinate bed of granite contained in mica slate. The mica slate is the predominant rock of the country. It is fine grained and contains an abundance of small garnets. Direction of the strata north and south varying a little easterly; inclination perpendicular. The bed of granite is about three hundred feet long and from five to twenty feet broad. It is contained in a narrow ridge of mica slate which descends into and is lost in a valley. The sides are precipitous; the highest part is about forty feet high. On the east side a considerable part of the granite hag been destroyed by natural causes leaving the granite bare. The granite consists chiefly of granular feldspar with grain of white quartz, and a little light coloured mica, is moderately fine grained, and of a grayish white colour.
In addition to tourmaline, it contains also emerald, some of the crystals of which are from three to five inches in diameter. I succeeded in getting one out of its matrix which is three and a half inches in diameter and its summit which is a plane without any additional facettes is perfect. The tourmalines are contained chiefly in a false vein of silicious feldspar and quartz, which begins in the centre of the upper edge of the bed of granite, and passes obliquely descending to the northeast, about twenty feet, where it is intercepted from sight by the mica slate. The vein is about one and a half foot thick in the upper part and not more than six or eight inches where it is lost. This vein of silicious feldspar contains also a vein of bluish white transparent quartz which is from three to eight inches thick and passes through the centre of the vein of feldspar. ...
The green tourmalines vary from one eighth of an inch to one inch in diameter; they are sometimes four inches in length and are entirely confined to the inner vein of quartz. They are triedral prisms, with convex faces, striated longitudinally, and generally traversed perpendicularly to the axis, with very small fissures filled by some silicious substance, probably feldspar. These green crystals are opaque. The red tourmaline is frequently enclosed in the green. In certain parts of the vein almost every green crystal encloses a red one, which always corresponds by its sides and angles with the exterior crystal.
References
| 1. | http://books.google.com/books?id=69vp6hRgxv4C&pg=PA268&lr=&as_brr=1&sig=8QhObRdZdytr8xGfc4IJr_VcRV4#PPA268,M1 |
| 2. | http://www.ndsu.nodak.edu/instruct/isern/103/salt.htm |
| 3. | "Investigation on the Rock Guano from the Islands of the Caribbean Sea", WM J Taylor, Proceedings of the Academy of Natural Sciences of Philadelphia 1858 |
| 4. | Hey's Chemical Index, 3rd Edition - entry for Pyroguanite |
| 5. | Meyers & Stewart, 1956. Geology of NH, Part III, p.57, 59 |
| 6. | The Penny Cyclopedia (1835), entry for 'Beryl' |
| 7. | "On the Tourmalines and other Minerals found at Chesterfield and Goshen, Massachusetts" by Col George Gibbs, American Journal of Science (1818) p.346 |
