Isinglass for Dummies - The Freelance Files MMCXLVIII

muscovite sample

Whenever we hear the word "isinglass," we're transported back decades to when we first heard "Surrey with the fringe on top" from the musical Oklahoma. According to the lyrics, the surrey had "isinglass curtains you could roll right down / In case there's a change in the weather." Apparently someone wanted to know, "What Is Isinglass?" and googled it. WiseGEEK was right there to "answer" at their AllThingsNature.org niche, courtesy of multiple nominee Malcolm Tatum.

Tatum, here collecting his sixth DotD award, pounded out a couple hundred words rife with his usual half-fast misinformation. Oh, Malcolm got the basic definition right:

"More properly known as muscovite, isinglass is a form of mica..."

...but then immediately went off the rails with this rather strange comment:

"...that is often found in sheets."

We guess that's Malcolm's remembrance of the physical geology class he too decades ago. In fact, muscovite (like all micas) is always found in sheets, because the micas are a class of mineral known as "sheet silicates." Samples of mica part easily along a single cleavage plane, like pages of a book. Ergo, Malcolm's "often found" is utter bullshit.

Tatum then claimed that, 

"Such minerals as kyanite, feldspar, and topaz are often cited as building blocks for the creation of isinglass."

To that comment, the staff geologist could only say, "WTF, Malcolm?!" It took some reading to understand that Tatum came up with that misinformation when he tried to reword part of a sentence from Wikipedia,

"Muscovite is... found... as a secondary mineral resulting from the alteration of topaz, feldspar, kyanite, etc."

Yeah, no, Mal: the first half of the sentence said that Muscovite is found in granite and pegmatite, the latter a far more likely source of the large sheets once used by Russians instead of glass. The alteration of other silicate minerals to muscovite results in tiny flakes of mica, not large "books." Going back to Malcolm's first paragraph, however, we were astounded to be told that,

"The sheets are often very thin, transparent, and somewhat elastic in nature."

Based on that sentence, it's pretty clear that Tatum didn't (and probably still doesn't) know what "elastic" means. He apparently thought that it meant "flexible"; it doesn't. It means "stretchy," and isinglass is not at all stretchy, although it's flexible if thin enough.

And finally, Tatum's "research" led him to make this claim:

"Around the city of Moscow, the material is often used for window glass. The particular formula that is used to create these clear and tinted panes is known as Muscovy-glass."

We aren't certain what a "particular formula" is, but we will point out that the term "Muscovy glass" dates to the Elizabethan era, when glass was difficult to make and therefore expensive. Russians don't use isinglass windows nowadays, Mal!

Given the vast amount of misinformation and misinterpretation contained within his post, should it be any wonder that Malcolm is a Dumbass of the Day again? We don't think so. 

SI - MINERALS