Ella, I have used a medium gray Velour like material works well. The
rest of this advice is predicated on your making color prints at a
local automated color photo lab.
Purchase a Kodak Gray Card and set the exposure from the card . Then
place the jewelry on a like colored medium gray Velour . Do not
change the camera setting. Although photographers backdrop samples 2’
X 2’ square have been given to me , I still like the medium gray .
If you have no control over the quality or setting of the photoshop
printers used, it has been my experience that the automatic printers
will make the back ground look like the 18 % gray of the Kodak Gray
Card. Sadly the local photo shop at Wal - Mart has untrained and
I have purchased a book and video from Charles Lewton Brain which
goes into much more detail . If I were living somewhere that had a
decent photo lab, I would use Mr Brain’s book " SMALL SCALE
PHOTOGRAPHY " much more.
ROBB - Retired Old Baby Boomer