What Are Half-Integer-Spin Geons and Their Significance in Nature?

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I did some casual reading on WP about geons. I understand that they have only been studied classically, and in a classical theory of course their angular momentum wouldn't even be quantized. But they were apparently intended as a candidate for the ultimate building blocks of nature. In that case, I don't understand where the half-integer-spin particles would come from, since you can't generate half-integer angular momentum from orbital motion. Anyone know anything about this?
 
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