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Thank you for article. I’m currently writing a book on physical properties of the BOM plates per witness accounts (81 total): material; plate size and thickness; book thickness, weight, and binding; writing script, language; seal portion; and other characteristics. I handle the witnesses individually and then do collective reconstruction.
Some Initial Comments:
1. Plate size (Part 1, Step 1).
Witnesses described plates between 6″ square (S.F. Anderick, 1888) and 12″ square (Josiah Stowell, 1832). Most witnesses described a length between 7″ and 9″, and a width between 6″ and 7″–which are the same or very close to your figures.
2. Plate thickness (Part 1, Step 2).
It’s nice to know someone else figured out that of “common tin” refers to tinplate (See my comment on 3 Jan 2025 on Dan Vogel, “Joseph Smith Brings the Plates Home – Dan Vogel”, https://www.youtube.com/watch?v=mmX-H1GBivk). Thickness for tinplate ranged from about 0.3 to 0.9 mm (0.012 to 0.035 in.), making your minimum value of 0.005 in. in Step 2 too thin. Note that your footnote 21 to Barrett et al regards paper, not parchment.
3. Tumbaga (Part 1, Step 2).
You state: “These finding [gold and copper alloys in the Old and New World] provide historical context for the possibility that such an alloy was used in the creation of the plates.” To posit Tumbaga is problematic. There was no metallurgy in Mesoamerica (where most scholars locate the BOM) before 800 CE, plus tumbaga was used for jewelry and religious objects.
4. Void Space (Part 1, Step 4 / Appendix D).
Your fabricated discs (0.02 in) had a void ratio of 53%. That seems very high. I contacted Bill McKeever who has a plate replica and the void ratio of sheet metal plates (23 gauge, 0.027 in.) is about 8%. Because void ratio has a huge impact on the possible results, it requires more research/experimentation. Note that Jerry Grover in “Ziff, Magic Goggles …” (2015, p. 90) cited sheet fragments from Columbia between 800 to 1250 AD had a “measured variation” of 6.3% to 39%.
Your experiment used “pure copper rounds.” Half hard copper is likely a better match for ancient copper (Grover, “Ziff,” p. 89)
5. Writing properties (Part 2)
I’ll need more time to work through your data and then compare to:
* Neal Rappleye’s FAIR presentation, “Comparing the gold plates to known ancient artifact,” 15 November 2023, https://www.youtube.com/watch?v=eAgzJ8MYrcw
* Jerry Grover interview on Mormonism With The Murph, “Could the text of the Book of Mormon have fit on the gold plates”, 27 February 2025, https://www.youtube.com/watch?v=qPwOZ7ZSLBc.
6. Text Size (Part 2, Step 1). David Whitmer (1831) stated “some of them [“characters”] large and some small.”
ken, see comments below:
>2. Plate thickness (Part 1, Step 2).
Thickness for tinplate ranged from about 0.3 to 0.9 mm (0.012 to 0.035 in.), making your minimum value of 0.005 in. in Step 2 too thin.
yes, the 0.005 minimum is in reference to 19th century “parchment” – not tin. there are at least two references to paper-like materials used to compare to the thickness of the plates. for the analysis of tin, see table 3 and appendix E in the paper.
>3. Tumbaga (Part 1, Step 2).
You state: “These finding [gold and copper alloys in the Old and New World] provide historical context for the possibility that such an alloy was used in the creation of the plates.” To posit Tumbaga is problematic.
the plates, as described by the 19th century documentary record and based on the math, are unlikely to be made of 100% gold. the possible valid configurations of pure gold require very large voids between plates and very short stacks of plates, and the ones with tinplate thickness result in a number of plates that leave very little room for the complete text. these 100% gold configurations just don’t work very well.
so if not 100% pure gold, then this leaves us with an alloy, and i’m unaware of any other ancient alloy that can produce a finish with the “appearance of gold” aside from gold/copper alloy, commonly known as “tumbaga”.
>There was no metallurgy in Mesoamerica (where most scholars locate the BOM) before 800 CE, plus tumbaga was used for jewelry and religious objects.
i have no interest in speculating about specific book of mormon geography, but metallurgy (specifically tumbaga work) is found in the old world as far back as 900 BCE (Valdez 2005) and is found in the new world as far back as 2000 BCE (Hauptmann 2016) and recall that nephi was from the old world.
>4. Void Space (Part 1, Step 4 / Appendix D).
Your fabricated discs (0.02 in) had a void ratio of 53%. That seems very high. I contacted Bill McKeever who has a plate replica and the void ratio of sheet metal plates (23 gauge, 0.027 in.) is about 8%.
yes, 53% is very high compared to modern manufacturing flatness standards specified by the ASTME. bill mckeever used modern metal sheets manufactured to a level of precision which is not applicable to understanding ancient sheet metal.
>Note that Jerry Grover in “Ziff, Magic Goggles …” (2015, p. 90) cited sheet fragments from Columbia between 800 to 1250 AD had a “measured variation” of 6.3% to 39%.
as i read it, grover indicates that scott (Scott 2000) measured the thickness of ancient sheet metal and found a variation of 6-39% in its thickness, which does not tell you anything about its flatness. without a measurement of its flatness, variation in thickness will tell you nothing about the size of the void between stacked sheet metal. you would need to measure the variation in flatness, not thickness, and i would be very surprised if scott measured this, and i would even more surprised if the size of the metal he was measuring was anywhere near the size of a plate from the book of mormon. the larger the size of the sheet metal, the higher the void will be due to increased variability in the flatness.
>Your experiment used “pure copper rounds.” Half hard copper is likely a better match for ancient copper (Grover, “Ziff,” p. 89)
“half hard copper” is simply annealed copper, which is what was used in the experiment of the 165 copper rounds, and i’m not sure why you think annealed copper would be a better match for ancient copper? both ancient and modern copper are easily annealed as well as work hardened.
i would welcome additional experimental data on non-commercially manufactured flat plates and the void between stacks of them, but for now, the 165 copper disks is the only experimental data i’m aware of.
thank you for reading the paper, your feedback, and your interest in the subject. 🙂
Thanks for your quick response.
Void Space.
I think void space is an important factor which has not been explored. The reason I contacted Bill McKeever was to get the lower limit for the void space–nothing would be lower than modern produced plates which looks to be around 8%.
In your experiment, the copper rounds were “machine roll[ed], hammer[ed], anneal[ed], stress reliev[ed], and descal[ed].” Do you have any information about material properties (tensile strength, hardness), flatness of each sheet, weight applied during “manual compression.”
(Any expansion of Appendix D would be helpful.)
We’ll never know the exact void space, but as more people do research and experiments and analyzing the data, hopefully it will produce subsequent experiments that will nail down the likely range of the void space.
Hello Josh. Interesting paper. With regard to Appendix F and the “Lost 116 Pages” you indicate the D&C’s stating “more particular” as meaning a “more detailed” account in the small plates. I would then ask, how could Nephi be “more detailed” about Lehi’s writings, than Lehi was? I take the D&C to mean Nephi was more detailed about his own account of “these things” which would include abbreviation of Lehi’s Dream and blessings and expanding on those and a LOT of borrowing from Isaiah, but Don Bradley makes a compelling case in his book, “The Lost 116 Pages: Reconstructing the Book of Mormon’s Missing Stores,” for there being many more than 116 pages from the book of Lehi that were stolen. Would factoring in Bradley’s figures impact your findings? You ruled out anything over 116 pages when translation time is factored in. What if you ruled out everything less than 116 and nothing greater than 300 (Bradley p.95)? Just curious. Thanks for giving me some new things to think about.
Maggie, Josh will have to answer for himself. I will just note that we didn’t have Lehi’s writings. Even in 1 Nephi, Nephi abridged them. We might assume he did so on the other plates. However, the other plates were also more attuned to political themes, so perhaps they were not. In any case, the wild card is that we didn’t even have what Nephi wrote on the large plates, but only what Mormon thought was important. So, details could easily be lost.
maggie,
it’s certainly possible that “more particular” could mean something besides “more detailed” – though the examples of the term used in elsewhere in the book of mormon seem to indicate that it means something similar to “more expansive” though it’s up to interpretation.
i don’t know how many manuscript pages were lost – the traditional number is 116, however, as you noted, bradley has various estimates above this number – but it’s important to note that for the calculations in the paper the unit of ‘pages’ is too imprecise and so the unit of ‘characters’ is used instead.
so to account for various estimates of the length of the “116 pages”, the range of sizes that were included in the calculations start at *half* the size of the small plates of nephi (about 180,000 characters) all the way to *twice* the size of the small plates of nephi (about 720,000 characters.)
bradley suggests that a single page of the printers manuscript is equivalent to 1.15 pages of the modern printing of the book of mormon. assuming this, then the 116 pages is about 133 pages of the book of mormon, or just less than the modern printing of the small plates of nephi, which is a little over 142 pages in length. using this metric, this aligns with the idea that the lost pages were slightly shorter than the small plates of nephi, which also seems to be supported by the internal evidence in the scriptural text.
however if we assume the lost pages were closer to 300 manuscript pages in length, then in a modern printing they would be about 345 pages, which is over twice the length of the small plates of nephi.
the calculations that are included in my paper don’t quite go that far in accommodating an estimate that large, but they come close (about 284 pages instead of 345). see figure 7 in the paper for what this looks like.
but to answer your question, yes, there are many valid physical configurations of the plates that assume 345 pages in the lost pages. they just tend to have smaller text sizes, higher translation densities, thinner plates and more of them.
Just curious but would the method of inscriptions affect the size of characters? Such as a pointed scriber or a chisel with a mallet?
brian,
i have no particular expertise in the various ancient methods of metal engraving, but i have some experience in working with depletion gilded tumbaga. the outer layer of gold on a depletion gilded tumbaga item is relatively thin – just a number of microns in thickness, and making marks, such as characters, does not require the force of a mallet, but it is labor intensive and tedious.
as to how different methods of engraving may effect the size characters, i could only guess.
Josh, thanks for your article. While Moroni tells us that “we [likely Mormon and Moroni only] have written this record … in the characters which are called among us the reformed Egyptian,” he also tells us that the characters were “altered by us according to our manner of speech.” (Mormon 9:32) In other words, the characters that they used for writing were not the same as in the beginning of the record. While it is very possible that the authors of the small plates of Nephi used the Demotic script for their record, Mormon and Moroni many hundreds of years later certainly did not, as Moroni told us; they used an altered script that he called “reformed Egyptian.” So, there would have been at least two different scripts present on the plates: Demotic (possibly) and reformed Egyptian, whatever that looked like. Another reason that “reformed Egyptian” could not have been Demotic is because Moroni was clear to add that “the Lord knoweth the things which we have written and also that none other people knoweth our language.” (Moroni 9:34) Late Demotic script was still in use in Egypt at the time that Moroni scribed his final words.
loren,
i agree that the type of writing used in the small plates was probably different than the type of writing that mormon and moroni used hundreds of years later. i also agree that reformed egyptian is not demotic – but note that the analysis in the paper does not assume demotic was used on the plates. demotic, being a type of ancient egyptian written language, is simply a reference point for translation density in the analysis.
“YHWH” in the paleo-Hebrew 600 BC Ketef Hinnom inscription on silver amulets was about 0.3 inches long (7.62 mm) — https://library.biblicalarchaeology.org/article/words-unseen/ .
Your average estimate of 5mm square (3.9mm Table 13; 5.4 to 2.5mm Table 12) “with each character representing at least three English characters, similar to Egyptian Demotic” is absurd because Demotic does not always need more than one character (see cursive examples in Nibley, Since Cumorah, 2nd ed., 149). Hieratic and Demotic Egyptian can be used as “short-hand” (Champollion’s tachygraphie) in which one squiggle can represent an entire common phrase. “And it came to pass,” for example, is five English words which is written with one word in Hebrew (ויהי four Hebrew letters vocalized wayehi), but which could be presented in Demotic as one squiggle for ḫpr.f “it came to pass, it happened” (Chicago Demotic Dictionary H3 50-54), and which has a number of analogs in the “Caractors” Transcript. In Coptic it is written out as ⲁⲥϣⲱⲡⲉ ⲇⲉ “it came to pass.”
Naturally, names and important words could be spelled out in longer forms. The use of logograms would have saved space, which is the very rationale for using reformed Egyptian (Mormon 9:33) instead of alphabetic Hebrew.
robert,
ancient inscriptions on metal have been found to be as small as less than 1mm and as least as large as 9mm. tables 12 and 13 simply show examples of valid calculations which include 2.5mm and 5.4mm characters which are within the range found in extant ancient artifacts.
as for demotic, the paper is simply evaluating the average number of demotic characters and comparing them to the average number of english characters in an english translation of that demotic text. the fact that some demotic characters may represent more or less than an english word is not relevant to the calculation. see appendix B in the paper for more information on this.
This is incredible research! Thanks to Josh for putting this together
thanks ben. 🙂