a poem
Jonathan Swift's "A Modest Proposal"
A polished piece refers to a finished work that has been refined and perfected through editing, proofreading, and revising. It is free from errors, flows smoothly, and is ready for publication or presentation.
A short story that has been workshopped and revised. (Apex Sociology)
Jewellery stamping is when a piece of jewellery is stamped to identify the type of metal which has been used; for example "750" means the metal is 18 carat gold.
I believe you are describing a prism.
boilers
Polished
a mirror due to the fact of being reflective.
A polished diamond is an example of complete diaphany, in that you can see through it.
black polished granite is the best and long lasting.
gears on heavy equipment
Diamond. Diamond is, for example, polished with diamond powder.