Basalt fiber?

This sounds too good to be true, from a lunar perspective:

"In their physical properties (strength, elasticity) basalt fibers
considerably exceed mineral and glass fibers. Due the elasticity of
micro- and macrostructure, basalt fibers are vibration-resistant
compared to similar products. This property is of particular
importance in mechanical construction and civil engineering. For
example, when buildings are erected near highways, railways and
underground, whereas under vibration cushions of mineral and glass
fibers experience damage and finally disintegrate, basalt slabs are
vibration-resistant and, hence, more durable."
http://www.basaltfibre.com/eng/

I was thinking that it would be simpler if the radiation shielding
could bear its own weight, rather than having to remain stationary
(so as to be weightless) while the colony rotates inside it as in
the Summer Study plan. My first thought was that glass fiber seems
like a reasonable material for radiation shielding, given the
abundance of its constituent elements. But if you can make fiber
straight from basalt, that would be much easier.

This might limit the radius of the habitat, compared to designs
where only better structural materials are weight-bearing. If so,
that would mean that they have to be more numerous rather than
bigger.