Ceramic Petrography

December 5, 2017 | Author: Murray L Eiland | Category: Earth Sciences, Geoarchaeology, Archaeometry, Ceramic Petrography
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Deskripsi Singkat

ROCK & GEM

Ilotv Archaeuloulsts

Idmtify ilfiinerals ln Anclent Psttery f E.

bv fuIurray Eiland tthough

*rn, o.nri. are ta-

miliar with nooular archaeolo-

f[ ru;,i:t; ll';';ls, &il',,'ii;

fivdre of the growing utility ol the earth sciences when applied to cerarnic materials. The premise is simple: By using a microsoope to identily minerals in ancient pottery. we can begin to understand ancient trade, as well as how (and perhaps why) cer-

tain kinds of ceramics wele made. But belore \\e go on lo consider our particular methids of study, it is best to define the questions we want to answer. For many the most interest-

ing question is trade. Various vessel forms made of clay

have been exhaustively studied for many years. ancl l'or rnany cultures

there exists u classiiication that can-in ideal circumstances-yield a

date lor the level in question. For instance. il one l'inds pottery ol a particular kind scattered around a statue tthat may be hard lo dale). one may be able to date the statue, because it is associated with the pottery. Ceramics are a per-fecl tool tbr dating. as once thev are fired thev survive weathering. In many sitei several tons of potlery shardi can be recovered in a normal season of excavation. Today in rnany ancienl citier in the Near East, one can find literally thousands ol pottery lragments Iittered about the surfaie. "Traditionul" archaeologists who study vessel shapes rely upon being

able to identify particular traits in

pottery that difl'er over time. For,example, a vessel lip may thicken,'so that if we find'pottery ia the level, be. /or.r., with a thin lip, and pottery in the upper letel with a thick lip, then we can place the two into a scquettt'e date-tha|" is, one pot was made belore another. Using othel materials that are near where we found the vessel. we can corelate a vessel with

lip to a certain date based upon coins, inscriptions. or radiomet-

a thick

ric (C-14) dating. At another site, perhaps near the hypothetical site just considered, if we, find similarlooking pottery with a thick lip, we may conclude that the pottery was made at about the same time. It seems that styles ol pottery. like modern auto designs, change from year to year, even if we are consider. ing cars from places as far apart as' the U.S. and Germany;

It is not too mrch to say that this method of dating, established during the last century, is the basis for many archaeological dates. For many sites there are literally thousands of drawings oi pottery fragments. It is. then. not unusual to have a situation where a pottery I'ragment is clezrly not related to others found at the same site. This hypothetical fragment is totally different. Instead of being a jug, like most of fhe other pots, it is a beaker No other pots have a sqratched decoration on the surface or are a distinct pink color. In such a case ue may place this vessel into another category. the "imported" category. continued on next pdge

Mav 1997

m ffi

THE NATURAL HISTORY CATALOG from SFS Quality fossils, minerals, rocks, opals, gemstones, teaching aids, artifacts, antiquities and more-at reasonable prices!!

of lip sesign ses ,gn

pr

sand or crushed rocks mixed into clay

cross-section

ol

\

nr

simple handle

sh_ -' o.d- -.I o"=I . -I v i o:io

='^y

'{

..,

tt,;-

a:. lb, -- 1. t.

lo-'-t:-l

5.o ', -o'ui] t.la-

I

hr

-,'{

"bi

S...b

:',,'l ' -. r'u

no decorations on pot exterior

tl

pl

Ci

sI a

ot \)

Celebrating our 1Oth year serving collectors, schools and museums. Thanking you for past and future business.

^: L]

pr

s. -r, t': r, )^a

rt

c

Ir

Visa/Mastercard accepted

1-800-688-6721 To receive our 1996 catalog and to be put on our mailing list for quarterly speciality items and news, just send $2 to:

Southeastern Fossil Supply Company 1205J North Eastman Road Suite 209 Kingsport, TN 37664 ($5 discount on first order) lf you are in East Tennessee, stop at Collectors Paradise 134 Broad Street, Kingsport, TN Antiques to Dinosaurs - lt's like a museum where everything is for sale!!

rt

Cooking Pot (circa 150 B.C. - A.D. 250)

pi

al

Ceramic/

pr

from page 65

later, during the Parthian occupation

(l50 e.c. to e.o. 250). What is

Perhaps intended to contain a substance to be taken by a trader over a distance. the vessel is now all that remains of this ancient trade. But was this vessel made a few miles away? Or was this vessel transported by ship across vast distances? [n order to answer this question convincingly, we must turn to the earth sciences. Who can really be sure that a

local potter did not simply make

a

of pot? Luckily for pottery studies, few clay

strange kind

vessels were rnade of pure clay. Because

clay is basically feldspar mixed with water, it shrinks when it is dried and undergoes significant changes when fired. Ancient people understood that, in order to make clay vessels, they had to add other substances, mineral or vegetable. To make the clay more workable so that it could be modeled and even placed on a wheel and then fired, other materials were added to the clay. Sand or crushed rocks are a perfect temper, as they do not

shrink like clay. Much like a modern composite material, the resulting clay pot

is actually a combination of different substances with different characteristics. By identifying mineral temper under the microscope, we form a better under-

standing of whether a vessel was made locally or was imported, depending upon the craft habits of that particular region. One of the most convincing aspects of looking at the minerals in a clay vessel, rather than simply generating a chart of how much of each element is present in the sample-as in chemical analysis is that pictures are convincing. Two interesting examples of trade are a pair of "cooking pots" recovered from the site of Nineveh in modern lraq. This is the familiar site as mentioned in the Bible, although the period studied here is

interesting about the first sample is that it is clearly different from all other wares. Unlike the majority of shards from this site now in Western museums, this sample is of a black fabric, with white grains as temper. When this shard was cut and ground into a slice that could be examined under a microscope by transmitted light, it was clear that these white grains were calcite, and perhaps the most interesting aspect of the grains was that they were angular. This implies several things. First, that the grains have been recently fractured, probably by a human agent. Anyone who

is familiar with calcite knows that it would not survive for long in nature as angular grains. It can therefore be ruled out as a natural component of the clay. The second aspect is that the calcite indicates that this vessel was not exposed to temperatures above 850 degrees Celsius, as above this temperature the mineral would have undergone transformation into other species. All the grains of calcite examined from the other shards from this site were clearly heated to a higher temperature, and no shard had nearly as much calcite as this example. Perhaps the next question to ask would be, Why would this vessel be imported? It is ugiy, and why did anyone need to import cooking vessels? Attempting to answer such a question elicits a few surprises. The first is that visual clues, such as how a pot looks on the surface, are not always reliable guides. Some pots can look exactly alike to the

et

II

ir

sl

rl

L

IT

Si

o' pi a1

tL

p!

St

CI

cl

bi

if

hr

fr

CI

l:

gr

tl

kr

fr

hr

st

a(

k

C'

pi

ir

eye, yet, one group will clearly have come from another place. The other sur-

br

prise is that not only beautiful pots are

aI

transpofied. In some cases it is the ugliest, coarsest pottery that has been transported over miles for use as a cooking

ROCK & GEM

S(

SI

1T

'L

pot. There are particular qualities one wants when using a cooking pot, and one

of the most important is that the pot will not suddenly explodel Although this is still an area that is receiving scientific study, it seems that calcite is very well suited for use as a temper in a cooking pot. When exposed to

it matches the clay body in expansion (heating) and contrac-

heat, and then cooled,

tion (cooling), so that little stress is

UERSATUME

.

Newly

.

AC/DC-0peratesoneither thancoroetitivemodels

.

Bedesigned . 40% More UV 0utput

ACpoweradaptorsystem

.

Lifetimelilters

0r4 "AA"

.

4 watts

batteries

0l power

.

color is also significant, as all other

switchable wavelength

Nowavarlablein export m0dels

. Liletimelillers . 12 ol povyer truatts

seleGt EimeP uen$alumc 0n nauteGton u ltln all Y0un uu llcGd$

parisons with similar shards from other areas, archaeologists have found cooking pots of this type in other pafis of Northern Iraq, near the ancient site of Nineveh.

Several Models Available

It would seem from what little evidence we have so far that this vessel was made in nearby Syria. Out of several thousand shards from Nineveh and other sites, these vessels were clearly cooking pots. Unlike the image of a rare, carefully made pot that was made to hold expensive cosmetics-or perhaps stand on its own artistic merit-this coarse cooking pot wams us against assuming too much. Another example of a ware, that from all appearances is imported, is similar to the above cooking pot, but has some impofiant differences. In this case, the vessel has a iedge handle instead of the curved handle of the shard above. The clay used in this pot was reddish, and the base of the pot is smudged with soot-as

wire craft jewelry on the net al

COMPLETE SCHOOL OF WIRECRAFT JEWELRY Instructor:

Master Wire Sculptor Preston J. Reuther The techniques introduced in this series demonstrate an easy-to-learn method of making handcrafted wire jewelry that wiU amaze you. With Preston's method you v/on't need years of experience before you create dazzling jewelry with only a few simple tools' .

.

if it

were placed in a fire-but the base has clearly been weakened by fire and fractured. In a thin section under the microscope, this shard had temper that was

U

. AC/DC Rechargable . Dual tube with

placed on the ceramic matrix. The black shards from this site are a grey/buff color. When the clay itself (as opposed to the temper) was analyzed chemically, it was very different from the other shards. In this case, examination under the microscope and chemical analysis show that this sample was imported. In com-

NOYIEllItlR Newly Redesigned

tntro to wire scutpture part ntro to w re scu prure Part

1

,

. scurpted pendants part l - Sculpted Pendants Part, : : :

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;

::'lot*

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:::li[:

xiffi: ::1

3

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1 video and .5O for each additional video. LA residents tax. PLUS!!!! Buy all 9 videos for $399.OO plus $7.95 S&H.Visa/MC

completely different. There are very large (even some 3 millimeters long)

To order: Preston J. Reuther . Phone 504-649-6505 . tr.ax 504-641-5144 or send check or money order to 106 Hwy 19O tr/est A-4 Suite 142R, Slidell, LA 70'46,0

grains of alkali basalt with titanium aurgite. Like the calcite in the above shard,

[Foreign orders add $1O.OO plus S&H; MC, \IISA, International money order.)

the grains were fractured. As anyone who has worked with basalt and calcite knows, the latter is considerably easier to

fracture than basalt. Could the basalt have been waste from making grinding stones or building stones that was simply

"SWEET SIXTEEN" SAMPLE BOX GET TO KNOW OUR GEODES and NODULES . . . SIXTEEN beautiful cut and polished geodes and nodules!

added to pottery? While we may never

know the answer to that question, it

An excellent variety containing:

would seem that this vessel was less successful than the calcite tempered example; perhaps this could be considered an imported cooking pot that failed. This article can do little more than present some highlights of ongoing research, but it should be clear that there is a huge amount of material to study, and that from studying pottery using the earth sciences,

we can come closer to understanding many aspects of an ancient [email protected]

,

Two New Chalce Geode Halves

. .

.

Two 0cotilo Geode Geode Halves Halves r One Galaxy Two Chihuahua (Trancas) Halj Geode Geode Halves 2 Tamaxa Geode Two Bola-Bola Geode H alves Halves These range in size lrom 2" to

o Two Coconut

.

. .

one Coconut Nodul€ Hall Two Zacatecas Geode Halves

approximately 3Y2".

16 HALVES l0r $51.00 Postpaid in the U.S.A. Write lor out relail price list Dealerc wite fot wholesale prices

Miimum order $51.00 Texas residents please add 8o/o sales tax.

GEM CENTER U.S.A., IIIG. 4100 arameda Avenue, Er Paso, rexas ,t:li; E]ii.tii#il

i

I ,

May 1997

67

1

I

i

ll

IIililffiLilil[ilI]llllll till[l



Deskripsi

ROCK & GEM

Ilotv Archaeuloulsts

Idmtify ilfiinerals ln Anclent Psttery f E.

bv fuIurray Eiland tthough

*rn, o.nri. are ta-

miliar with nooular archaeolo-

f[ ru;,i:t; ll';';ls, &il',,'ii;

fivdre of the growing utility ol the earth sciences when applied to cerarnic materials. The premise is simple: By using a microsoope to identily minerals in ancient pottery. we can begin to understand ancient trade, as well as how (and perhaps why) cer-

tain kinds of ceramics wele made. But belore \\e go on lo consider our particular methids of study, it is best to define the questions we want to answer. For many the most interest-

ing question is trade. Various vessel forms made of clay

have been exhaustively studied for many years. ancl l'or rnany cultures

there exists u classiiication that can-in ideal circumstances-yield a

date lor the level in question. For instance. il one l'inds pottery ol a particular kind scattered around a statue tthat may be hard lo dale). one may be able to date the statue, because it is associated with the pottery. Ceramics are a per-fecl tool tbr dating. as once thev are fired thev survive weathering. In many sitei several tons of potlery shardi can be recovered in a normal season of excavation. Today in rnany ancienl citier in the Near East, one can find literally thousands ol pottery lragments Iittered about the surfaie. "Traditionul" archaeologists who study vessel shapes rely upon being

able to identify particular traits in

pottery that difl'er over time. For,example, a vessel lip may thicken,'so that if we find'pottery ia the level, be. /or.r., with a thin lip, and pottery in the upper letel with a thick lip, then we can place the two into a scquettt'e date-tha|" is, one pot was made belore another. Using othel materials that are near where we found the vessel. we can corelate a vessel with

lip to a certain date based upon coins, inscriptions. or radiomet-

a thick

ric (C-14) dating. At another site, perhaps near the hypothetical site just considered, if we, find similarlooking pottery with a thick lip, we may conclude that the pottery was made at about the same time. It seems that styles ol pottery. like modern auto designs, change from year to year, even if we are consider. ing cars from places as far apart as' the U.S. and Germany;

It is not too mrch to say that this method of dating, established during the last century, is the basis for many archaeological dates. For many sites there are literally thousands of drawings oi pottery fragments. It is. then. not unusual to have a situation where a pottery I'ragment is clezrly not related to others found at the same site. This hypothetical fragment is totally different. Instead of being a jug, like most of fhe other pots, it is a beaker No other pots have a sqratched decoration on the surface or are a distinct pink color. In such a case ue may place this vessel into another category. the "imported" category. continued on next pdge

Mav 1997

m ffi

THE NATURAL HISTORY CATALOG from SFS Quality fossils, minerals, rocks, opals, gemstones, teaching aids, artifacts, antiquities and more-at reasonable prices!!

of lip sesign ses ,gn

pr

sand or crushed rocks mixed into clay

cross-section

ol

\

nr

simple handle

sh_ -' o.d- -.I o"=I . -I v i o:io

='^y

'{

..,

tt,;-

a:. lb, -- 1. t.

lo-'-t:-l

5.o ', -o'ui] t.la-

I

hr

-,'{

"bi

S...b

:',,'l ' -. r'u

no decorations on pot exterior

tl

pl

Ci

sI a

ot \)

Celebrating our 1Oth year serving collectors, schools and museums. Thanking you for past and future business.

^: L]

pr

s. -r, t': r, )^a

rt

c

Ir

Visa/Mastercard accepted

1-800-688-6721 To receive our 1996 catalog and to be put on our mailing list for quarterly speciality items and news, just send $2 to:

Southeastern Fossil Supply Company 1205J North Eastman Road Suite 209 Kingsport, TN 37664 ($5 discount on first order) lf you are in East Tennessee, stop at Collectors Paradise 134 Broad Street, Kingsport, TN Antiques to Dinosaurs - lt's like a museum where everything is for sale!!

rt

Cooking Pot (circa 150 B.C. - A.D. 250)

pi

al

Ceramic/

pr

from page 65

later, during the Parthian occupation

(l50 e.c. to e.o. 250). What is

Perhaps intended to contain a substance to be taken by a trader over a distance. the vessel is now all that remains of this ancient trade. But was this vessel made a few miles away? Or was this vessel transported by ship across vast distances? [n order to answer this question convincingly, we must turn to the earth sciences. Who can really be sure that a

local potter did not simply make

a

of pot? Luckily for pottery studies, few clay

strange kind

vessels were rnade of pure clay. Because

clay is basically feldspar mixed with water, it shrinks when it is dried and undergoes significant changes when fired. Ancient people understood that, in order to make clay vessels, they had to add other substances, mineral or vegetable. To make the clay more workable so that it could be modeled and even placed on a wheel and then fired, other materials were added to the clay. Sand or crushed rocks are a perfect temper, as they do not

shrink like clay. Much like a modern composite material, the resulting clay pot

is actually a combination of different substances with different characteristics. By identifying mineral temper under the microscope, we form a better under-

standing of whether a vessel was made locally or was imported, depending upon the craft habits of that particular region. One of the most convincing aspects of looking at the minerals in a clay vessel, rather than simply generating a chart of how much of each element is present in the sample-as in chemical analysis is that pictures are convincing. Two interesting examples of trade are a pair of "cooking pots" recovered from the site of Nineveh in modern lraq. This is the familiar site as mentioned in the Bible, although the period studied here is

interesting about the first sample is that it is clearly different from all other wares. Unlike the majority of shards from this site now in Western museums, this sample is of a black fabric, with white grains as temper. When this shard was cut and ground into a slice that could be examined under a microscope by transmitted light, it was clear that these white grains were calcite, and perhaps the most interesting aspect of the grains was that they were angular. This implies several things. First, that the grains have been recently fractured, probably by a human agent. Anyone who

is familiar with calcite knows that it would not survive for long in nature as angular grains. It can therefore be ruled out as a natural component of the clay. The second aspect is that the calcite indicates that this vessel was not exposed to temperatures above 850 degrees Celsius, as above this temperature the mineral would have undergone transformation into other species. All the grains of calcite examined from the other shards from this site were clearly heated to a higher temperature, and no shard had nearly as much calcite as this example. Perhaps the next question to ask would be, Why would this vessel be imported? It is ugiy, and why did anyone need to import cooking vessels? Attempting to answer such a question elicits a few surprises. The first is that visual clues, such as how a pot looks on the surface, are not always reliable guides. Some pots can look exactly alike to the

et

II

ir

sl

rl

L

IT

Si

o' pi a1

tL

p!

St

CI

cl

bi

if

hr

fr

CI

l:

gr

tl

kr

fr

hr

st

a(

k

C'

pi

ir

eye, yet, one group will clearly have come from another place. The other sur-

br

prise is that not only beautiful pots are

aI

transpofied. In some cases it is the ugliest, coarsest pottery that has been transported over miles for use as a cooking

ROCK & GEM

S(

SI

1T

'L

pot. There are particular qualities one wants when using a cooking pot, and one

of the most important is that the pot will not suddenly explodel Although this is still an area that is receiving scientific study, it seems that calcite is very well suited for use as a temper in a cooking pot. When exposed to

it matches the clay body in expansion (heating) and contrac-

heat, and then cooled,

tion (cooling), so that little stress is

UERSATUME

.

Newly

.

AC/DC-0peratesoneither thancoroetitivemodels

.

Bedesigned . 40% More UV 0utput

ACpoweradaptorsystem

.

Lifetimelilters

0r4 "AA"

.

4 watts

batteries

0l power

.

color is also significant, as all other

switchable wavelength

Nowavarlablein export m0dels

. Liletimelillers . 12 ol povyer truatts

seleGt EimeP uen$alumc 0n nauteGton u ltln all Y0un uu llcGd$

parisons with similar shards from other areas, archaeologists have found cooking pots of this type in other pafis of Northern Iraq, near the ancient site of Nineveh.

Several Models Available

It would seem from what little evidence we have so far that this vessel was made in nearby Syria. Out of several thousand shards from Nineveh and other sites, these vessels were clearly cooking pots. Unlike the image of a rare, carefully made pot that was made to hold expensive cosmetics-or perhaps stand on its own artistic merit-this coarse cooking pot wams us against assuming too much. Another example of a ware, that from all appearances is imported, is similar to the above cooking pot, but has some impofiant differences. In this case, the vessel has a iedge handle instead of the curved handle of the shard above. The clay used in this pot was reddish, and the base of the pot is smudged with soot-as

wire craft jewelry on the net al

COMPLETE SCHOOL OF WIRECRAFT JEWELRY Instructor:

Master Wire Sculptor Preston J. Reuther The techniques introduced in this series demonstrate an easy-to-learn method of making handcrafted wire jewelry that wiU amaze you. With Preston's method you v/on't need years of experience before you create dazzling jewelry with only a few simple tools' .

.

if it

were placed in a fire-but the base has clearly been weakened by fire and fractured. In a thin section under the microscope, this shard had temper that was

U

. AC/DC Rechargable . Dual tube with

placed on the ceramic matrix. The black shards from this site are a grey/buff color. When the clay itself (as opposed to the temper) was analyzed chemically, it was very different from the other shards. In this case, examination under the microscope and chemical analysis show that this sample was imported. In com-

NOYIEllItlR Newly Redesigned

tntro to wire scutpture part ntro to w re scu prure Part

1

,

. scurpted pendants part l - Sculpted Pendants Part, : : :

:::i3[: 3::::iff ::i

;

::'lot*

Hings Part

1

:::li[:

xiffi: ::1

3

$59.95each. S&H $3.95 for a;dd 4o/o sales

1 video and .5O for each additional video. LA residents tax. PLUS!!!! Buy all 9 videos for $399.OO plus $7.95 S&H.Visa/MC

completely different. There are very large (even some 3 millimeters long)

To order: Preston J. Reuther . Phone 504-649-6505 . tr.ax 504-641-5144 or send check or money order to 106 Hwy 19O tr/est A-4 Suite 142R, Slidell, LA 70'46,0

grains of alkali basalt with titanium aurgite. Like the calcite in the above shard,

[Foreign orders add $1O.OO plus S&H; MC, \IISA, International money order.)

the grains were fractured. As anyone who has worked with basalt and calcite knows, the latter is considerably easier to

fracture than basalt. Could the basalt have been waste from making grinding stones or building stones that was simply

"SWEET SIXTEEN" SAMPLE BOX GET TO KNOW OUR GEODES and NODULES . . . SIXTEEN beautiful cut and polished geodes and nodules!

added to pottery? While we may never

know the answer to that question, it

An excellent variety containing:

would seem that this vessel was less successful than the calcite tempered example; perhaps this could be considered an imported cooking pot that failed. This article can do little more than present some highlights of ongoing research, but it should be clear that there is a huge amount of material to study, and that from studying pottery using the earth sciences,

we can come closer to understanding many aspects of an ancient [email protected]

,

Two New Chalce Geode Halves

. .

.

Two 0cotilo Geode Geode Halves Halves r One Galaxy Two Chihuahua (Trancas) Halj Geode Geode Halves 2 Tamaxa Geode Two Bola-Bola Geode H alves Halves These range in size lrom 2" to

o Two Coconut

.

. .

one Coconut Nodul€ Hall Two Zacatecas Geode Halves

approximately 3Y2".

16 HALVES l0r $51.00 Postpaid in the U.S.A. Write lor out relail price list Dealerc wite fot wholesale prices

Miimum order $51.00 Texas residents please add 8o/o sales tax.

GEM CENTER U.S.A., IIIG. 4100 arameda Avenue, Er Paso, rexas ,t:li; E]ii.tii#il

i

I ,

May 1997

67

1

I

i

ll

IIililffiLilil[ilI]llllll till[l

Lihat lebih banyak...

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