The deepest grief

[Mark A Becker]

Hey busker-

The deepest grief
Is like a thin layer of clay -
one side footprints
the other smooth as glass.

I like that the title is also the first line of the poem.
This is a tough subject for a short form poem. 

I immediately thought of grief as a kind of shell (having experienced grief on several occasions).

Being me, I would shorten this one even more: 
has one side soft as clay (malleable)
the other hard as glass (fragile)
The simile in the first line became a bit confusing for me when the second line introduced footprints.

Once again, grief is a tough subject to address is such a short form.  Hope not outta line with my suggestions...
/// Mark