Mansoor Amarna Collection

Robert E. Arnal,Ph.D. Report

From San Jose State University, Department of Geology

Robert E.Arnal

Three sculptures, now in the collection of Mr. E. Mansoor, were examined recently with the purpose of determining :

  1. If the rock of which they are composed is a natural rock or if it is even in part artificial; and,
  2. If they are authentic sculptures or forgeries made recently.

The reason of the doubt about their authenticity stems from the conclusions of a report dated April 14, 1949 and entitled "Technical Examination of Tell El Amarna objects, property of Mr. William Mansoor". In this report the author summarizes his conclusions by stating that :" the weathering of the surface is a forced one..." and that, in his opinion "the pieces in question are of fairly modern origin". This and other reports on the same subject will be reviewed at the end of the present report.

Description of the sculptures : Three sculptures labeled Mansoor 53, Mansoor 27 and number 137 were examined thoroughly. The two sculptured heads and the full statuette are composed of a pink rock showing here and there some whitish irregular patches. Mansoor 53 is a head about 4 inches high and about the same from the tip of the nose to the back of the head; it is partly broken in such a way that half of the forehead and part of the right cheek have been removed, the chin however is left complete. Number 137 is also about 4 inches high and nearly 6 inches from the tip of the nose to the back of the head; it is a complete unbroken sculpture. Mansoor 53 is a woman's head whereas number 137 is that of a man. Sculpture Mansoor 27 is a statuette representing the complete body of a princess, it is over 12 inches high and broken obliquely through the calves; the stand and the remainder of the legs bear a different number # 244. The tip of the nose is chipped off.

Macroscopic examination : Macroscopic examination shows the three sculptures to be made of a fairly soft pink rock which can be scratched easily with a knife. The rock shows indications of weathering to a variable degree. Head 137, for instance, shows a marked weathering effect on the face, the forehead, and the top of the skull, these parts of the head have a fairly smooth appearance. On the contrary, the back of the head is not as much weathered and has a rougher less polished aspect. Both the highly weathered and less weathered surfaces, however, are darker and have an aspect quite different from a freshly scraped surface which shows a lighter pink color with a very dull luster. The separation between the smooth weathered surface on top of the head and the rougher less weathered surface on the back of the head is so irregular and so transitional that it cannot be artificial; it looks exactly like what one would expect from natural weathering.

The sculpture has the appearance of being exposed to weathering action in such a way that the back of the head would be on the leeward side of the direction from which the weathering agent was acting; or else the back of the head was partly buried and protected for a certain period of time. This stopped that part of the head from acquiring such a smooth weathered surface as that of the remainder of the head which was exposed to the weathering agent. The same effect may be observed on head 53 in which the part which has been broken off is not so much weathered as the sculptured part. Sculpture 27 shows also a smooth weathered surface for all the protruding parts of the body whereas all the re-entrant angles are not as smooth and somewhat lighter in color.

The weathering of the 3 sculptures is exactly alike that of some concretions which I collected in the desert of Southern California. In these concretions, the lobate protruding portions which are exposed to a sort of sand blasting weathering ( due to wind action ) appear smooth and somewhat shiny whereas all the buried parts are rougher and very dull.

The comparison of the sculptures with concretions of the Southern California desert is appropriate since the climate there is almost identical to that of Egypt where the sculptures were found.

Rock composition : As the pink rock of which the sculptures are composed is fairly soft, I tested it to find out if it could be a limestone. Dilute hydrochloric acid treatment, washing and decantation were applied to a known quantity of rock previously weighed accurately with a chain balance. The insoluble residues were weighed after drying. The results show that the rock is effectively a limestone containing about 80% of calcite. The remaining 20% represent the amount of insoluble residues.

Some of the reddish inclusions are made of siderite, the iron carbonate; limonite, the iron hydrous oxide, and some maganese oxide are also present.

Microscopic examination ; Under the microscope, using 60 magnifications, the pink limestone appears disseminated throughout with limonite. It contains very abundant shells of microscopic animals called Foraminifera. These animals were living on the bottom of the ancient sea where the limestone was deposited. Shells of Foraminifera are made of calcium carbonate and probably form as much as 50% of the rock which may be termed an organic limestone.

The limonite is not of secondary and subsequent deposition but was precipitated at the same time as the limestone was formed. This can be demonstrated easily by breaking open the shells of the Foraminifera. These contain within the shell some limonite which proves contemporary deposition of this mineral and of the limestone.

The white patchy portions of the rock which may be seen here and there are not at all artificial as it has been alleged. They represent an inherent part of the rock since they also contain shells of Foraminifera. This would not be so if it were an artificial filling.

The limestone shows all indications of mechanical weathering due to the friction of sand grains thrown against the limestone by wind. This is typical of desert conditions. The following evidence indicate desertic conditions of weathering:

  1. The limestone still contains abundant limonite; if it had remained in more temperate and more humid climate, most of the limonite would have been leached and washed out of the limestone.
  2. Some of the cracks of the rock still contain some of the sand and silt which produced the mechanical weathering. I took care to remove for detailed examination the material trapped in one such crack and cleaned up the one located about one inch directly in front of the right foot of the sculpture labeled # 244. This material is mostly quartz particles, the size of the individual grains varies between 20 and 100 microns ( one micron equals 1/1000 of a millimeter ), this is a size well within the range which can be carried by wind. The particles are fairly well rounded and somewhat frosted which is another characteristic of particles of quartz carried by wind.
  3. Most of the shells of Foraminifera are protruding from the rest of the limestone and are somewhat shiny; this was produced by the friction of the sand grains against the shells. Friction must have lasted a fairly long period of time as the ornamentation of the shells is somewhat obliterated and worn out. The shells of Foraminifera are protruding because of their size ( several hundred microns ) much larger than that of the particles forming the limestone which are no more than a few microns. The successive layers of fine particles of limestone which are merely packed together but not cemented have been dug around the shells of the Foraminifera by the sand blasting action of the quartz grains. Being much larger in size, the shells of the Foraminifera remain embedded until all the limestone is removed down to the base of the shells. The following diagram helps to understand the process. The size relationship of the different particles is kept in the diagram.

Carbon tetrachloride test :It occurred to me that the patina which has a shiny appearance could have been made by rubbing some greasy material on the sculpture. This would produce a shiny surface on all protruding part of the sculpture. In order to test this idea, several parts of the sculpture were rubbed with carbon tetrachloride which is a good solvent of greasy material. Absolutely no change was observed and this alternative must be eliminated. Besides, this type of artificial patina would not leave the shells of Foraminifera protruding out of the limestone as it is the case. Some other artificial patina could be made by use of dilute acid, this method certainly was not used because the shells of Foraminifera would have been the first part to be dissolved. They would not be protruding out of the limestone as it is definitely true of all sculptures examined.

Other sculptures examined : In addition to the 3 pieces previously mentioned about 7 others were examined rapidly with a hand lens giving about ten magnifications, these other sculptures were made obviously of the same rock containing the same types of Foraminifera. They show the same lithologic characteristics including the lighter whitish patches, the limonite marks and the dendrites of manganese oxides. Belonging to the same group these sculptures were not examined any further and what was said for the 3 sculptures examined in detail, holds true also for the other ones. Without any doubt they are made of the same limestone.

Another sculpture of a much larger size representing the bust of a king was also examined. It is made of a yellowish white limestone, but under the magnification given by the hand lens it was impossible to say if that sculpture contained any Foraminifera within the limestone, the rock of which the sculpture is made is somewhat different. However there is a point which can be stated definitely about this sculpture, namely that the rock is not artificial and does not contain any artificial patches. True there are some inclusions of lighter color which might look artificial, however there is a structure among these inclusions which permits to say that they are inherent parts of the rock. Several of these patches are crossed by fractures starting in the main body of the rock on one side of the inclusion, going through it entirely and continuing some distance on the other side. These fractures are completely crossing the inclusions and are filled with calcite in their entire length; this type of microstructure was present before the rock was quarried and therefore make it impossible for the inclusions to be artificial.

Evaluation of previous reports : I have read three reports evaluating the sculptures of the Mansoor collection. The excellent report of Professor Compton, Stanford University, is obviously that of a well qualified geologist. He brings several good lines of evidence, especially concerning the mechanical weathering, which favors strongly the authenticity of the sculptures. The report of Dr. Zaki Iskandar dated Nov. 28,1950 is very extensive and indicates a broad knowledge of Egyptology. All his conclusions also favor the authenticity of the sculptures.

On the contrary the report of Mr. Young of the Boston Museum is mostly the expression of an opinion based on very weak evidence to say the least. The conclusions are based on examination under Ultra-Violet light. Ultra-Violet light might be a good mean to determine the authenticity of ancient sculptures, if care is taken to recognize the limitations of the method. Obviously the method used by Mr. Young refers to that developed by Mr. James J. Rorimer of the Metropolitan Museum of Art ( use of a Corex A filter under U.V. rays ). The method is explained in some detail in the February 1934 issue of " Industrial and Engineering Chemistry " page 235. Two important remarks may be made from reading the article: 1. that it is used mostly to evaluate the age of marble sculptures, and 2. that it has been successfully applied to the study of Grecian and Roman Marbles. Both of these remarks need additional comments. Regarding the use of this method to check marbles, it must be pointed out that marbles are calcium carbonate rocks in which the calcium carbonate is well crystallized in large crystals. This is one of the reasons why the method is working for this type of rocks because as mentioned in the above article page 235 " after years of exposure the individual crystals are not as firmly held together in the surface of the marble as they are 0.25 inch below the surface ". The fact that the crystals are not firmly held together is what permits to recognize the characteristic disintegration; in the instance of the Tel-el-Amarna rock we are in presence of a limestone and not a marble. The limestone of Tel-el-Amarna is an organic limestone made of an agglomeration of fine size particles ( a few thousandth of a millimeter ) of calcium carbonate and other non carbonate material associated with a great percentage of Foraminifera of which the shells also are made of calcium carbonate. In other words, the limestone of Tel-el-Amarna does not contain any crystals of calcium carbonate large enough and abundant enough to permit a good evaluation of its weathered characteristics by the U.V. method. Regarding comment number 2 the method has been applied successfully to Grecian and Roman marbles. The method has been applied to rocks which have been exposed to weathering action in temperate climate ( Greece, Rome ) where the amount of rainfall is such that chemical and physical reactions will take place on the surface of a rock exposed to the weathering elements. In desertic regions such as Egypt the rainfall is so small that it would take fifty to 100,000 years to achieve the same chemical weathering effect which is produced in temperate climate in a period of a few hundred of years. Therefore, if a piece of rock is exposed to chemical weathering in Egypt for a period of 4000 to 5000 years, it will be much less chemically weathered than the same piece of rock exposed to chemical weathering in Greece for the same period of time. This being established, it can be understood why the ultra-violet method would not detect any weathering effect since the method observes changes produced by chemical weathering. These are practically inexistant or at least very small in desertic climate over a period of 4 or 5000 years. Furthermore H.J. Plenderleith of the British Museum writes along the same line when he warns users of the ultra-violet method to be very cautious in its use and states : " It is often possible by examining a piece of marble sculpture to determine whether it is recent or ancient and to reveal any modern cutting on an old marble, but as there can be no absolute guide as to the time required for a marble to acquire a patina recognizable as ancient, it is impossible to date marbles by the quality of their fluorescence ". Obviously, Mr. Plenderleith, the keeper of the research laboratory of the British Museum, does not consider the fluorescence method very reliable, even when applied to marbles.

Regarding the artistic value of the sculptures, I am not qualified to express an opinion, however, that of Mr. E. Drioton, one of the foremost expert in matters of Egyptology is positive enough to clear out any doubt about the authenticity of the sculptures.

A translation of a letter written by Mr. E. Drioton is given for interested parties who are not acquainted with the french language.

Conclusions: I will summarize my conclusions by saying that :

  1. The sculptures are made entirely of natural rock which contains no artificial filling.
  2. The weathered surface is a natural one and was produced over a long period of time.
  3. The fluorescence method is not reliable and any opinion on the authenticity of these sculptures based on the use of this method should be disregarded.
  4. The artistic value of these sculptures has been established by one of the foremost expert in the field.
  5. It can be stated that these sculptures are authentic and of ancient origin.
( Robert E. Arnal )
March 7, 1959
San Jose State College
San Jose, California.

P.S. The following are the references used in the present report.

Colin G. Fink 1934, Chemistry and Art. Industrial and Engineering Chemistry Vol. 26, no. 2,pp.234-238.

H.J. Plenderleith, 1956 The Conservation of Antiquities and Works of Art, London, Oxford University Press, page 315.

Cabinet d'Egyptologie
College de France
Place Marcelin Berthelot
Paris ( 5eme )

Montgeron January 3,1959

Dear Mr. Mansoor,

Being a federal employee of the French government, member of the Artistic Council of the Museums of France and professor at the College de France, I am not permitted, as you know to give you an official evaluation of the Amarna sculptures that are in your possession. However I know them very well, inasmuch as I had the chance of studying them often in your father's house during the many years that I spent in Egypt as general director of the Service des Antiquites.

My personal opinion regarding these sculptures is made. I do not see any reason why I could not repeat it again and I even give you permission to make it known confidentially if this could be helpful to you : I think they are authentic sculptures.

The report of Mr. Lucas who was the most eminent specialist in matter of egyptology and also the one of Professor Robert R. Compton of Stanford University ( in contradistinction to the report of Mr. W.J. Young of the Boston Museum ), are positive about this subject. I may add that, concerning the artistic point of view, these sculptures come from a workshop related to, but not identical with, the one in which the colossuses of Karnak were executed. Their stylistic pattern, advanced in the same fashion as the Karnak Sculptures, is of such a full faultless execution that it cannot be, in my opinion, the work of a forger.

I remain, dear Mr. Mansoor,

Sincerely Yours,

Signed : Etienne Drioton

Translated by Robert E. Arnal
San Jose State College
San Jose, California
March 7,1959