#1 The making of an animal-shaped weight in old Myanmar by Banning 09.06.2015 03:48

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Maybe I'm the only one interested in this, but ever since I began to dig into the history and purpose of Burmese weights, I’ve been curious about their rigorous standardization and yet striking variability across weights. I couldn’t quite reconcile the wonderful craftsmanship and blatant flaws that I saw in each weight. Donald and Joan Gear cover it (as with just about everything else), but I find the chapter a little weak. Also probably because I'm a trained industrial designer and care about manufacturing.

R.C. Temple donated his collection of weights and associated paraphernalia to the Pitt Rivers Museum in Oxford, which is kind enough to feature it online. Temple captures his curiosity in the subject in his writing for the Academy (Volume 38, July-December 1890): “The weights were cast by the cire perdue process, the cores being of wax previously run into deeply sunk iron dies. I have a complete set of the “peacock” weights of Mindon and Thibaw, with cores and dies. Very little, however, so far as I am aware, is known about this subject, and I can do no more than draw attention to it as worth studying.”


If you've made it this far, you might be interested in the process. I expected each individual wax core to be made one at a time by a craftsman, but instead they had a pretty terrific manufacturing process where each bird weight wax core was made of 3 simpler molded wax pieces:
BirdHalfWax1c.jpg - Bild entfernt (keine Rechte)
BirdHalfWax2c.jpg - Bild entfernt (keine Rechte)
BirdBaseWax2.jpg - Bild entfernt (keine Rechte)

They would essentially be assembled as follows:
LostWaxOpiumWeight.png - Bild entfernt (keine Rechte)

And later placed into a clay mold like the following:
Mold2.jpg - Bild entfernt (keine Rechte)
Mold1.jpg - Bild entfernt (keine Rechte)

All of this was surprising to me as I really didn't catch it in reading Earth to Heaven and it gave more to look for when examining my weights.

For one, you begin to see how the two pieces of wax created this flaw underneath the tail of the bird (you'll have to look closely):
BirdJoint2.jpg - Bild entfernt (keine Rechte)

And you can also see the how the melted wax pooled a little and created a joint on the leg of a bird (again, look in close):
BirdJoint1.jpg - Bild entfernt (keine Rechte)

Not sure this is the right forum for these types of observations as fodder for a conversation. If it is, I've also begun to see some specific regional differences in weight origins – at least when sourcing them – that I'd be happy to chat about as well.

#2 RE: The making of an animal-shaped weight in old Myanmar by jack326 09.06.2015 07:15

Great post regarding the manufacturing process of weights. Your post helped clarify the weight making process. Been trying to find more information about the process without much luck. Your post with photos fits perfectly within the forum! Thanks for posting! Jack326

#3 RE: The making of an animal-shaped weight in old Myanmar by Banning 09.06.2015 07:19

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Jack – I keep on thinking that I'm coming up with something new, but really it's all (buried) in the Earth to Heaven book. Glad you liked it!

#4 RE: The making of an animal-shaped weight in old Myanmar by white elefant 12.06.2015 00:32

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Thanks for your post, your description and the detailed images.

Even if one can find very attractive weights among this group, I think, especially the last Burmese weights (H3A1, H3A2, H3B and the H3 bird weights produced after 1885 respectively in the areas already occupied by the British after 1826) were partly made with less care. Therefor somtimes you will easily find the traces of manufacture and correction in weight mass and form.

The weights (lion and birds as well) cast prior to 1820 and the weights (birds) of the Shan-States were made more accurate and with more effort and craftsmanship.

A few years ago, preparing the article for Arts of Asia (Beauty and the Beast - Special Burma Issue, May - June 2013), I've got the great chance to see a simply wonderful, impressive "Opium Weights" collection.
Parts of this collection were also a couple of soapstone moulds from the Shan-States were the wax models were shaped in, instead to be formed free by the hands of the craftsmen in the ancient times.
And one could be quite sure: They were used till the present day to produce some very beautiful Hintha 4D weights for the collectors looking for a "perfect" weight.

As you see, the wax models of H4D-weights were produced for halves inclusive the base but also for single parts, body, base and legs separate, then joined and completed.



fig. 1* Three different soapstone moulds forming one half of a weight


fig. 2* Two halves for a complete H4D weight


fig. 3 50 % of a beautiful decorated master piece



fig. 4* A smaller but nice one



fig. 5* A mould for the animal only without the base



fig. 6* All "spare parts" separate: base, wings, legs


*All images (c) Rolf Braun collection
Many thanks to Rolf Braun for the explicit permission to publish the images in the forum.

Any comments are most appreciated!
Thanks in advance!
Michael

#5 RE: The making of an animal-shaped weight in old Myanmar by Banning 12.06.2015 01:02

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That's wonderful, Michael. Thank you to you and Rolf for sharing!

#6 RE: The making of an animal-shaped weight in old Myanmar by Peter 18.08.2015 14:07

Thank you all for the illustrative photos and interesting discussion. Another thing that has puzzled me a bit is how the makers of these weights were able to ensure that their products were consistently accurate in terms of weight. Presumably, they would have needed to take great care to ensure that the alloy used contained exactly the right mix of copper, lead, tin, etc. I also suppose that, as the alloy in use changed over time, it would also be necessary to change the molds used, as well.


Another question I have relates to allowable variations in weight. It appears to be generally accepted that these weights can become a bit lighter over long periods of time and through repeated wear and tear. What about the allowed 'ceiling'? If we accept the15 gram/tical low standard and 16.3 gram/tical high standard as posited by Hartmut Mollat, what should we consider to be the upper range, acceptable margin of error for each standard, beyond which a weight should be viewed as not genuine?

#7 RE: The making of an animal-shaped weight in old Myanmar by Banning 29.08.2015 23:45

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Hi Peter. I trust the moderators of this site with a more educated opinion on the subject.

If you reference Earth to Heaven by Donald and Joan Gear, they provide a table with statistical deviations of weight distribution across 596 weights. They group them by time periods (that Mr. Mollat doesn't entirely agree with) that range from 1-7, or from 1885-1385.

The outside range of what they've identified as genuine weights is +/-12-14% weight deviation. But this range is pretty extreme. 90% of all weights fit within the deviation of +/-6% of the period-specific defined Kyat mass.

I hope that helps!

#8 RE: The making of an animal-shaped weight in old Myanmar by Peter 31.08.2015 15:50

Yes, that is helpful. Thanks.

#9 RE: The making of an animal-shaped weight in old Myanmar by hartmutmollat 13.09.2015 17:26

Hi Banning,

the maximum loss of mass - I collected strongly worn weights intentionally - comes to ca. 9%. Including lead between the legs. That means at least two phases of abrasion. At a remote market in Burma I found a 5 Tical To 2 weight (prior to 1700) nearly unrecognisable by wear and tear but still in use. My impression was that the people did not care too much about the exactness of the weights. I do not know how the dealers managed to use 100 and 50 Tical weights with the handles broken that are not rare.

Best!
Hartmut Mollat

#10 RE: The making of an animal-shaped weight in old Myanmar by Peter 14.09.2015 01:28

Hi Hartmut,

Thanks again for your helpful contribution.

Based on your observations, did you reach any conclusions about the upper ceiling for percentage that a genuine weight could plausibly go over the standard grams / tical?

#11 RE: The making of an animal-shaped weight in old Myanmar by white elefant 20.09.2015 23:06

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Here are some examples to complement Hartmut's posting.
One can see that the strongly worn weights were usually readjusted with lead between the body and the base.
But even with lead, the weight mass we see today, differ from the target weight up to 8 %.
Where the readjustment is lost respectively where the weights never have been readjusted, the difference between the target and the actual weight mass could be slightly more than 10 %, in our example H3A2 12,4 %.


Chinthe 2B (775 g), Chinhte 2B (762 g), Chinthe 2A (718 g)


Chinthe 2B (with lead), Chinhte 2B (with lead), Chinthe 2A (without lead)


Hintha 3A1 (753 g), Hintha 3B (758 g)


Chinthe 1 (75 g), Chinhte 1 (72 g), Hintha 3B (143 g), Chinthe 1 (79 g), Hintha 4B (75 g)


Chinthe 1 (with lead), Chinhte 1 (without lead), Hintha 3B (without lead, just mud?), Chinthe 1 (with lead), Hintha 4B (without lead)

The results you find in the following table:

#12 RE: The making of an animal-shaped weight in old Myanmar by Banning 20.09.2015 23:47

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Is this not an instance that lends some credibility to Don and Joan Gear's tikal standard for Chinthe weights? As the adjusted weights would bring them close to the Gear standard of a 15.4g tikal for a Chinthe of that era (although I don't have my copy of their book in front of me).
-B

#13 RE: The making of an animal-shaped weight in old Myanmar by white elefant 21.09.2015 00:46

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I don't think so. If you see the weight mass of Chinte weights in the gallery's archive

http://www.opiumgewichte.com/index_gallery_Chinthe.htm

you will find, that the weight mass of the pieces in "perfect" condition is about 1630 g (more or less).
From my point of view, the question is, who did the readjustment and how precise he did it and finally, what was the duration of use after the readjustment and how much of the lead was crumbled away and lost until today.

Gear:
Chinthe 1 (group 2, period E): 15,4 g/tical
Chinthe 2 (group 2, period D): 15,7 g/tical

Here are two examples of Chinthe 1:


Chinthe 1, 100 tical / 1 viss (1.579 g) and Chinthe 1, 50 tical / 1/2 viss (786 g)

Already >15,7 g/tical, even slightly worn on the extremities.

#14 RE: The making of an animal-shaped weight in old Myanmar by Banning 21.09.2015 00:48

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Always a wealth of knowledge. Thanks!

#15 RE: The making of an animal-shaped weight in old Myanmar by hartmutmollat 21.09.2015 13:24

Hi Peter,

an addition to the discussion about standards: Every weight used for weighing has suffered a loss of mass. Therefore, the standard of an used weight is an individual standard which is in any case below the standard weight. Gear,s standards are all individual standards and cosequently too low. Since in Burma the old weight standard is still valid we can compare the idv. standards with the standard weight of 16,33 g/Tc. Michael showed an excellent survey on worn weights.

Many archaeologists determine the standard weights of old civilisations by forming the mean of several masses. Too low as well! If they will determine the mass of our kilogram in distant future in this way they will remain distinctly below 1000 g. We can estimate standard weights to be near (above) the heaviest weight of a weight class.

I found very rarely weights above the standard weight. They were two or three H4 weights maybe of local standards or of incorrect production.

Hartmut Mollat

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