Foul, foul! What am I?

Question

Despite being well-decorated, stylish, and sturdy
I'm often dark inside, and
When put into use, I am dark all around
I am destined to carry Something (that will soon turn foul)
To keep what is inside safe from what is without;
Not more than One in my lifespan
As It is often Something once precious and always remembered
But It grows much worse as time passes
Fouler, fouler
Until It becomes no more;
Even after It passes
I still remain covered
Filled and surrounded by dust
Till the end of Eternity
Or until I am pilfered
By some wretched soul

What am I?

Answer 1

This is

a coffin.

The lines are pretty much a direct description of the object:

it is dark, it carries a body (which will rot over time), and is placed in the ground permanently (unless grave robbers dig it up).