<p>"The fissures that lined its sides and the size distinguished it from many others; those whose extreme lavishness mocked the purpose of their existence." </p>
<p>"It" is referring to a honorary monument</p>
<p>Is this grammatically acceptable?</p>
<p>and can "whose" be used to describe inanimate objects?</p>
<p>Your use of “it” and “whose” appears to be OK. Here’s a grammar link on “whose”:
[Whose</a> for Inanimate Objects : Grammar Girl :: Quick and Dirty Tips](<a href=“http://grammar.quickanddirtytips.com/whose-for-inanimate-objects.aspx]Whose”>http://grammar.quickanddirtytips.com/whose-for-inanimate-objects.aspx)</p>
<p>However, your use of the semi-colon does not appear to be correct. If these are separate but related thoughts, you are missing a couple of words immediately following the semi-colon; if they are related thoughts, then you should replace the semi-colon with an em-dash (a long or double-dash).</p>