<PERSON>:
What might work for you is allotropes. That is, different crystalline structures for the same element. A famous example is graphite and diamond (both are pure carbon). Very different properties, exactly the same element. Here's the Wikipedia article on allotropy: https://en.wikipedia.org/wiki/Allotropy
<PERSON> novel Cat's Cradle uses a fictitious allotrope of water, he dubbed ice-nine, as a plot device. Actually, real water has a whole bunch allotropes, including 11 kinds of ice--depending on temperature and pressure, plus liquid, gas, and a weird phase at high temperature and pressure where there's no difference between liquid and gas. Here's a page about all the allotropes of water: http://www1.lsbu.ac.uk/water/water_phase_diagram.html
Another example of allotropy is pure tin. At room temperature it's the familiar shiny silver metal, but drop the temperature and the atoms rearrange themselves from octahedral to tetrahedral. The crystal swells up, becomes dark gray, brittle, and cracks apart. Check out this time-lapse video taken at -40°: https://www.youtube.com/watch?v=sXB83Heh3_c Note that the reshaping is reversible if you warm up your "tin pest," although you'll have little particles of the familiar silvery tin, not a big chunk.
Pure Plutonium is famous for it's extreme allotropy at room temperature, where it takes on 6 different crystalline forms. Never mind the toxicity and radiation, the stuff is hell to work with because it keeps shifting forms when you monkey around with it (such as trying to cast it, press it, machine it, etc).
So how might you use allotropy?
Pick an element that has the required abundance. 1) Crank the pressure waaaaaay up and raise the temperature too--your common element will rearrange itself into the perfect crystal form that's precisely what your story needs. 561
2) Hold the pressure and drop your temperature into the cryogenic region--crystal is still stable. 3) Hold your temperature and drop your pressure down to the normal normal region--still stable, but it'd never ever form under these conditions. 4) Raise your temperature back up to the normal region. Perhaps your new "cobalt-nine" (or whatever you call it) is semi-stable when treated this way. Maybe it looks nothing like the metallic cobalt we all know and love. Maybe it's a pale blue transparent crystal. But smack it with a hammer or zap it with an electric spark and it reverts back to metallic cobalt (just to be different, it should shrink as it does so).
Living things often concentrate and crystallize elements (e.g. teeth) and sometimes even the more exotic--such as tiny spindle-shaped crystals of magnetite in the brain--a built-in compass. Suppose some life form is able to create your "cobalt-nine" within it's brain, assembling the weird crystal atom-by-atom, and therefore gains telekinetic abilities (or whatever your story needs).
Maybe smart people figure this out and through experimentation they create synthetic "telkon" crystals and implant them into human brains. They work, but are unstable (break down) or toxic. Maybe the final answer is a thin coating of titanium (biologically inert) a few dozen atoms thick (or better yet titanium-nitride), before the crystals are injected.
Best of luck with your story. And consider using allotropes because we know so very, very little about them. Therefore you can just make stuff up and it will sound plausible.
These ideas freely given. 561