The Shatter Spell & Crystalline Creatures

[Ylissa]

Reviewing my Warmages spell list recently, I realised it includes the Shatter spell. Whilst I have seen the spell used a lot for shattering objcts, it struck me that I cannot recall the spell being used on a creature...

From the SRD wrote:

Targeted against a crystalline creature (of any weight), shatter deals 1d6 points of sonic damage per caster level (maximum 10d6), with a Fortitude save for half damage.

What exactly is meant by the phrase 'crystalline creature'? Are we talking creatures made from glass, or creatures with any crystalline structure (such as rock)?

Does anyone have any examples of creature that would be affected?

[Jeremy Mac Donald]

Crystal Creatures are pretty common if you play with psionics. You've got Crystal Golems and Crystal familiars etc. I think the shatter spell specifically means creatures made of glass and suchlike not rock. I'd use the kinds of thinks it effects when its not effecting a creature as a guideline.

[ArchLich]

I would classify crystalline as (for game purposes) made of glass, gems, or other large planed/faceted structures of mineral growth. Or something.

[Ylissa]

Sorry, should have mentioned I was looking for feedback for a non-psionic game.
Has anyone ever seen this spell cast on a creatures? If so, what was the target?