2501: Average Familiarity

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Average Familiarity
"How could anyone consider themselves a well-rounded adult without a basic understanding of silicate geochemistry? Silicates are everywhere! It's hard to throw a rock without throwing one!"
Title text: "How could anyone consider themselves a well-rounded adult without a basic understanding of silicate geochemistry? Silicates are everywhere! It's hard to throw a rock without throwing one!"


This comic claims that experts vastly overestimate how familiar other people are with their own field of study. As an example, Randall shows a conversation between Ponytail and Cueball as two geochemists specializing in silicate chemistry. Although the two scientists understand that the layman does not know all that they know about silicates, they are still under the impression that other people at least know the chemical makeup of olivine and some feldspars. Cueball also mentions quartz, an even simpler mineral taken for granted by Ponytail.

In truth, the average person can't be expected to know the chemical makeup of any arbitrarily-chosen substance reliably (or any material at all), if that average person's job and hobby do not involve chemistry — aside from the few that made their way into common knowledge, like NaCl for salt (sodium chloride or halite in mineral form), H2O for water (facetiously known as dihydrogen monoxide, ice in mineral form), or CO2 for carbon dioxide (while most people are more familiar with its gaseous form, it is also used in mineral form as dry ice), and may not even know the definition of "feldspar" beyond "a mineral", if at all.

It even goes so far as to initially gloss over the 'everyday' knowledge of quartz... until prompted by the slightly-less-overestimating partner in the conversation. Perhaps like a gardener forgetting to mention the lawn he maintains (along with the 'actual' plants in the borders or vegetable patches), there seemed no need to include such a common mineral as a subject of silicate chemistry. Quartz is a basic silicon oxide (SiO2) that many non-chemists have heard of because it is common and has a variety of uses, though they would not know its chemical structure. Quartz can be found as distinct large-scale crystals (probably obvious to the layman, as an ice-cube is in a drink) but also features as a hard-wearing micro-constituent of many rocks. Quartz is a major component of most sand (except for coral sands, which are calcium carbonates). Quartz crystals are sometimes made into jewelry and other decorative objects. Most modern clocks use the resonance frequency of quartz to keep time.

Minerals like feldspars and olivine generally exist as a continuum of varying chemical formulas, represented as a mixture of "endmembers" that have some pure composition. Feldspars are a category of aluminum-containing silicate minerals that account for the most of the rock in the earth's crust by mass. They are composed of a silicon-aluminum-oxygen lattice filled with sodium, potassium, or calcium ions. The major varieties are CaAl2Si2O8 (anorthite), NaAlSi3O8 (albite), and KAlSi3O8 (potassium feldspar). Olivine is most notable as being the primary constituent of the upper mantle and commonly found in stony meteorites, and has the formula X2+2SiO4, where X is any iron or magnesium ion. The ends of the spectrum are Mg2SiO4 (forsterite) and Fe2SiO4 (fayalite).

In the title text the two geologists express belief that the average person should be more familiar with silicates because of how ubiquitous they are. Their somewhat-exasperated statement plays on the phrase "you can't throw a rock without hitting one," a standard hyperbole about how common something is. Indeed, silicate rocks are extremely common on Earth — not only would a rock thrown in a random direction stand a decent chance of striking a silicate mineral rock, but the rock being thrown also has a very high chance of being a silicate mineral rock. With the exception of a few carbonate deposits, rocks found in large deposits on Earth's surface nearly all have silica in them, even extraterrestrial rocks. The Earth's crust is about 60% silica by weight.[1]


[Ponytail and Cueball are talking. Ponytail has her hand raised, palm up, towards Cueball.]
Ponytail: Silicate chemistry is second nature to us geochemists, so it's easy to forget that the average person probably only knows the formulas for olivine and one or two feldspars.
Cueball: And quartz, of course.
Ponytail: Of course.
[Caption below the panel]
Even when they're trying to compensate for it, experts in anything wildly overestimate the average person's familiarity with their field.


  1. "Constraining crustal silica on ancient Earth" C. Brenhin Keller, T. Mark Harrison. Proceedings of the National Academy of Sciences Sep 2020, 117 (35) 21101-21107; DOI: 10.1073/pnas.2009431117

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I've never even heard of olivine. I think most people have heard of quartz (it's the crystal in most electronic watches, and it's pretty), and I suspect feldspar is somewhere in between. Barmar (talk) 05:21, 12 August 2021 (UTC)

If you find a hard white rock, it's probably quartz; very common where I live. Decorative white pebbles? Quartz. Clear, pretty crystals might be the same compound, but they had to be pure to start with and they had to cool really slowly. (Unsigned by
Well, it helps if you play Dwarf Fortress. Olivine is one of the green stones (that only really has use as building material/decoration, but makes an impressive megaconstruction mayerial if you find enough of it to make that worthwhile), unlike quartz which features as raw 'gem clusters' more typically cut for decoration of mugs, crossbow bolts, etc. Of course, IRL, quartzes are so ever-present that they are very easy to forget except as fancy crystals (either for timekeeping in watches or timewasting in crystal healing) and as such you can actually find them almost anywhere (if you're not stuck on a desert island). 12:37, 12 August 2021 (UTC)
Man, DF is everywhere once you've started playing it. PoolloverNathan[talk]UTSc 17:44, 5 January 2023 (UTC)

I resemble this comic ... I specialize in probability. Does everyone know that probability=1 means 'certain'? ... I'm not certain ... (Unsigned by

In a general probability distribution, a probability of 1 means an event happens "almost surely" rather than "certainly" (see definition here). I know the distinction isn't important if one considers only finite sample spaces, but I think it's a cool enough concept that the nitpicking might be interesting to someone. 05:02, 13 August 2021 (UTC)
People who went through at least the first half of the math undergraduate program will most likely understand. In the general population, I guess, saying '100 % probability' would work much better than 'probability 1', but still people can get quite upset when something with 99 % probability of success fails, not understanding that 99 % (or even 85 %) does not mean guaranteed success (see for example 14:46 of this video about randomness in video-game design https://www.youtube.com/watch?v=dwI5b-wRLic). CryptoNut1269 (talk) 11:08, 12 August 2021 (UTC)

As a chemist, I heard of all of them but, fun fact, there is a mnemonic in the german language known by at least all of the elderly generation: "Feldspat, Quarz und Glimmer - die drei vergess´ ich nimmer!" thats "feldspar quartz and mica - i will never forget the three". These three are the main compunds of granite and obviously this was stuff they had to learn at school. If, in a group of silverheads, start the phrase "Feldspat Quarz und Glimmer ..." and there will always be someone to finish the sentence. --Pauliprinzip (talk) 05:45, 12 August 2021 (UTC)

and may not even know the definition of "feldspar" beyond "a rock". Ironically, I think the person writing this may have overstated the "average Joe"'s familiarity with the word "feldspar", since I couldn't have defined it if you'd asked me. --Enchantedsleeper (talk) 08:11, 12 August 2021 (UTC)

I got the idea that both Cueball and Ponytail were geochemists, rather than Cueball being just an average adult. OblateSpheroid (talk) 20:02, 12 August 2021 (UTC)

Seconded. Danish (talk) 20:12, 12 August 2021 (UTC)
I got the opposite. Isn't Cueball supposed to represent Randall himself, who isn't really geochemist? 01:19, 17 August 2021 (UTC)lizzardwizzard
I don't think Cueball always represents Randall. Danish (talk) 01:28, 17 August 2021 (UTC)
Yeah, but it sorta kinda fits in here, no? Like, I have no idea what minerals is she talking about, but! I know quartz! I'll say quartz! And add "of course", to pretend I know all that stuff. Well, could be both ways. I do not insist on my interpretation. 14:46, 17 August 2021 (UTC) lizzardwizzard

Seemed like the examples of substances the average person might reasonably know the chemical formula for should include a mineral. Halite seems likely (though that name is probably less familiar than table salt). Diamond and graphite were the only other minerals that I could think of that many would know the formulas for (C). Chalk (calcite) seems possible, but less likely. Any other suggestions (or even better, any citations to research)? 21:30, 12 August 2021 (UTC)

technically water in the form of ice is a mineral. But including salt is a good idea. And I'll look for citations. Curiouscat (talk) 21:44, 12 August 2021 (UTC)
Water is surely not a mineral in any useful sense. It is, instead, the simplest of monohydric chain-alcohols, with the formula of H-(CH2)N-OH for N == 0. Methanol is to it as ethanol is to methanol. As such, it is usually a very safe chemical to imbibe, although it's also often mixed with dihydrogen monoxide, hydric acid and hydrogen hydroxide as dangerous contaminants that it is very difficult to filter out. 05:40, 17 August 2021 (UTC)
I would expect lot of people would be able to name "formula" for more than several elements, along with having some idea how they look OR where they are used. Not as common knowledge as water and salt, but assuming they had SOME chemistry in school, this would be more likely to be remembered than compounds. Also, speaking about diamond, I suppose average people would claim that formula for coal is C, although I suspect that chemists would say that's not correct. -- Hkmaly (talk) 02:16, 13 August 2021 (UTC)
I probably wouldn't have been able to tell you the chemical formula for salt off the top of my head, unless you prompted me with "sodium chloride" (but even then, it's a toss-up as to whether I'd get the elements right). I studied chemistry for five years at secondary school and got good grades, but you'd be amazed at how little sticks when you have absolutely no need for it in day-to-day life. --enchantedsleeper (talk) 08:56, 13 August 2021 (UTC)

Friendly local geologist here, I made some changes especially to the third paragraph because a lot of the science was confusingly written and not really correct (desert islands tend to be made up of primarily silicates? Even volcanic ones. Basaltic rocks have silica in them too, that's what olivine is) I wasn't sure what to do with the second paragraph. It seems a bit unnecessary to talk about quartz so much, since it isn't that relevant to the comic. I was thinking it might be good to have an explanation of the difference between silicon the element, silica the mineral structure, and what all these minerals actually are might be more relevant? Or at least we could put up what some of the chemical formulas are for quartz and olivine and maybe like albite, anorthite, microcline to represent the feldspars. Curiouscat (talk) 21:40, 12 August 2021 (UTC)

I thought (in a prior edit, by someone, may have lost its clarity in subsequent edits by others but I don't have the patience to cross-compare it all) the point was that coral-sands are not silicates, so your classic "lump of 'sand' poking out of the sea" is sparse of the stuff you might want to thrown your rock at. And any suitable rocks, unless you go diving down in the surrounding oceon to rumage beyond the living coral to the seamount/extinct-and-eroded-volcano it has been growing upon. That said, there's a lot of variation out there, so maybe I'm thinking of a too-narrow subset of examples. 00:14, 13 August 2021 (UTC)
I never learned much about coral sands, that's interesting. I was taught that most remote islands are young volcanoes, and therefore made up of mostly basaltic rocks. Definitely low-silica, compared to continental rocks, but still silica-containing, so their sands are also silicious. I also know that some forams make silica-based shells and not carbonate-based ones, but I'm not sure how much forams ultimately have to do with the formation of coral reefs or coral sand islands. Curiouscat (talk) 02:21, 14 August 2021 (UTC)
Replaced "average Joe" with "average person"

Per https://en.wikipedia.org/wiki/List_of_terms_related_to_an_average_person this term is specific to the US, and introduces specificity unrelated to the comic. (talk) (please sign your comments with ~~~~)

It's pretty common on this wiki for explanations to throw English expressions like this at the reader and expect the, ah, average Joe to understand.
Also, how does one use Template:Unsigned? I've definitely misused it once or twice, but reading documentations for it isn't helping (and unfortunately this is not a script; reading the src doesn't help either). bubblegum-talk|contribs 05:33, 13 August 2021 (UTC)
I'm afraid I don't know, but can I say how cool your signature is??
Also, thanks to the person at the top who replaced "average Joe", as that did bother me too. --enchantedsleeper (talk) 08:44, 13 August 2021 (UTC)
The unsigned template should used like this: {{unsigned ip|}}, see above for result, except if by a known user, then {{unsigned|Kynde}} should be used, which would produce this (which I leave as my signature now) -- Kynde (talk) (please sign your comments with ~~~~)
You can also add the time/date: {{unsigned|Lupo|13:27, 13 August 2021}} for this result: -- Lupo (talk) 13:27, 13 August 2021 (please sign your comments with ~~~~)

I knew quartz (SiO2) and I recognize the other two, all from having an interest in rocks (and having a little kids-oriented geology book decades ago when I was a wee lass). But beyond quartz, water, and salt, the only other chemical formula that come to mind are acids: H2SO4 and HCl. Mostly from the old rhyme: Jonny was a chemist's son / but Jonny is no more / What Jonny thought was H2O / was H2SO4. :p

Oh, also FOOF ( https://blogs.sciencemag.org/pipeline/archives/2010/02/23/things_i_wont_work_with_dioxygen_difluoride ) 12:39, 13 August 2021 (UTC)

The explanation mentions carbonates as a notable exception to silicates, but sulfate minerals are widespread and economically important (and therefore ubiquitous in their finished forms -- e.g., gypsum -> plaster or drywall). Might deserve a mention? 17:20, 13 August 2021 (UTC)

I left sulfates out because you usually don't find them laying around on their own except in mines. They exist as deep subsurface veins of ore deposits, but on the surface, gypsum and pyrite and the like typically present as individual crystals in a matrix of feldspars or grossular quartz. Besides silicate rocks, carbonates are the only ones off the top of my head that you can find in huge quantities above ground without silica incorporated somehow. Curiouscat (talk) 02:21, 14 August 2021 (UTC)

If somebody can run perl scripts, there is a bot linked from User:DgbrtBOT that could resume autocreation of comic pages. While we're mentioning such things, are comics also published on twitter? would it be good to link the twitter discussions? sometimes an expert comments.

When somebody does the necessary to create the page for 2502: The answer is the double-dagger. (Then the silcrow, double-danda and pilcrow, in turn.) HTH, HAND. 23:19, 13 August 2021 (UTC)

NVM. Someone created the page. (But they haven't yet created the Talk page for it, and I still don't have permission to do so, as an IP-only person. Nor done the necessary for the "Next" button to appear above, which I think is a function of adding 2502 to the List Of Comics page or something...) 23:53, 13 August 2021 (UTC)
The User:DgbrtBOT page lists all the steps to get things working right. To get the next button to show up, it requires editing the LATESTCOMIC template to the latest comic number. Orion205 (talk) 00:51, 14 August 2021 (UTC)

Maybe it could be noted that feldspar (and after that, quartz) is the most abundant mineral in the Earth's crust (and there are two groups of feldspars, the alkali feldspars and the plagioclase feldspars, depending on whether they contain potassium or sodium/calcium, both containing many types: microcline, orthoclase, etc.), while olivine is the most abundant mineral in the Earth's mantle. I also found https://en.wikipedia.org/wiki/Silicate_mineral very clarifying to get an idea of the classification of all these minerals into nesosilicates, inosilicates, phyllosilicates and tectosilicates, depending on the dimensionality of how the silicate tetrahedra are linked together.

Also, slightly related to this might be the QAPF rock diagram, which occurs at the bottom-middle in 2251: Alignment Chart Alignment Chart. The Q stands for quartz, and the A and P stand for the two groups of feldspar (alkali feldspar and plagioclase felspar).

I've only heard of Olivine because of pokemon. - 07:19, 15 August 2021 (UTC)