Subject: why are the properties of Gallium considered unusual?

Hello,

Gallium is an unusual element as it has a low melting point, high boiling point 
and is denser as a liquid than as a solid, however I am unsure why. Gallium 
also has lots of other properties such as: Soluble in acids and alkalis, 
Density (5.91 g/cm³), Volatile however I am unsure how to class these into 
metallic properties and non-metallic properties.

If you could help, I would be very grateful.
Thankyou in Advance,
    Zoe Pearson

Re: why are the properties of Gallium considered unusual?