Hessonite garnet... maybe. Have you considered it might be a zircon?
I am sure those with the appropriate credentials will offer some
assistance.. but high RI and brownish red... sounds like zircon.
Hessonite is relatively rare.... brown[ish] is a fairly normal color
or Zircons.. hitting towards the red side is more unsual, but
Zircons do go that way.
Brown is really not something I would associate with hessonite..
orange like... not brown.
Then.. I ain't no expert here.