Lava Rocks for Dummies

Lava rock in firepit

If there's one thing we've learned from several years of paging through the posting of greedy freelancers, it's that nobody can ask a question so stupid that an eHow.com contributor will not attempt to answer it. Take, for instance, the question, "What Is the Composition of a Lava Rock?" Speaking from a purely scientific viewpoint, it's a nonsense question, because "lava" is the description of a rock's formation (crystallized from magma that reached the surface) and has little or nothing to do with its composition. That does not, however, mean that some English grad like Bethany Horne wouldn't try to "answer" it anyway; in a post now found at Sciencing.com.

It occurred to some of our staffers that perhaps the term "lava rock" was what was printed on the bag of landscaping material someone bought, or perhaps they were concerned that it might be toxic when making s'mores in their firepit. Of course, if you're interested in that question, the first result in a Google search will tell you, and we kid you not, that

"Lava rock is actually a solidified sponge..."

That's news to everyone here. At least Horne didn't get that stupid in her answer, although our geology types think she came darned close. They think that because she said crap like,

• "...magma [ is] a liquid rock material made up of minerals and gases..." – No, magma is just liquid, since minerals are solids. They are what crystallizes from magma when it cools.
• "Lava rocks are a type of igneous rock known as basalt, which is composed of various mineral and chemical elements." – Lava rock doesn't have a definition, at least geologically speaking, there are also other extrusive igneous rocks such as rhyolite and andesite. While we're here, though,  WTF does "various mineral and chemical elements" mean, anyway?
• "The composition of a lava rock is a function of its mineral structure and chemical arrangement." – Uhhh, no. The composition of a "lava rock," of whatever species, is a function of the composition of the magma, which is a function of the environment and the material melted to create magma. As for "chemical arrangement," we think she got confused about that's a rock and what's a mineral.
• "basalts... are the primary rock layer of the Hawaiian Islands." – Layer? What's this "layer" bullshit? Basalt pretty much makes up the entirety of the Hawaiian islands.
• "At high temperatures, the mafic minerals cool and crystallize very quickly. " – We think you mean relatively low temperatures, Bethany.
• "Lava rocks are porous, meaning they are filled with tiny holes or pores." – Well, the stuff sold as lava rock at Lowe's is porous, but that's because it probably isn't basalt. It's more likely to be scoria than basalt, and may come from just about any extrusive igneous rock, including cinder cone cinders.

True to her BA in English, Horne did little more than download and attempt to reword some "information" about basalt, confusing it with the general term "lava rock." That still might have worked if our Dumbass of the Day hadn't completely botched the rewording process...

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