Collateral

[MJK]

Hi,

I am new to Bitshares and crypto in general, so please excuse the newbie questions.

I am trying to understand how bitshares works and I read about how it is 300% collateralized. So for example, if i purchase 1 ounce of BitGold for $1200 worth of bitshares and after 6 months the price of bitshares went down 400%, how am i guaranteed that i will still get back my 1 ounce of BitGold?

Thanks
MJ