Calamitous
I am only a word of five letters, but I have caused great calamities. Take away my head and I enhance a city.
Behead me once more and I am a place where all the world once congregated.
If at first you curtail me, I am a mineral.
Curtail once more and I am a fashionable resort.
Yet if instead you cut off both my head and my tail it does not deteriorate my value.
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