Welcome to the wonderful world of metalsmithing... Be prepared to
fall in love with it!
Copper can be a wonderful material to work with, but it does have
issues with tarnishing and coloring as it is very reactive to pretty
It's likely that she used simply clear nail polish to seal the piece.
Depending on the design, when I work with copper I do use clear
acrylic spray (Klear Koat or RustOleum brands) in the desired finish
- gloss, matte, or satin. Occasionally, I will use nail polish, but
only on a piece where I'm sure that brush strokes in the polish won't
With most copper projects I do, however, I use patinas (heat or
chemical) because the colors can be so wonderful.
P.S. - You mentioned a concern that your teacher seemed "evasive"
about some of the materials she was using. It is, of course,
possible that she doesn't want to share her secrets....But it's early
in the class so it's more likely she just doesn't want to confuse you
with you're not ready for. For example, referring to
"japanese" metals refers to a range of usually custom alloys like
shibuishi (there are tons of them) with specific properties of
melting, reticulation, coloring, etc. She likely won't get into
making and using those alloys until much later in the course (or in
an advanced course) when you have the foundation of fabrication that
will help you understand and work with them.
Best of luck to you!
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