Diamond
A diamond is a rare and valuable gemstone. Grokko found a diamond worth 50 gold pieces along with a topaz, sapphires, emeralds, pearls, rubies, an owl feather and Detlef's journal in Detlef's lair beneath Senneborn.
Ser Reginald Kobolwitz wrote that he had wrestled a dragon and taken its diamond, although Vichthart found his writing pompous not to mention unverifiable. Vichthart later perused the Ravensfair market stalls for 200 gold pieces' worth of diamond dust so he could cast the spell Glyph of Warding, but this was of course far too rare and valuable for market stalls to stock.
When Mira recovered the valuables he lost to the mirror device in the Spire of Transmutation—106 gold pieces, 12 silver pieces, 6 copper pieces, 1 pearl worth 100 gold pieces, and 1 candlestick worth about 25 gold pieces—in the vault of the Acropolis of Kereskaa, he also found and took 3 diamonds. In the 3 days after the party defeated the Knives of Mystra and the bone devil beneath Karst, Mira got these appraised as having a combined value of 500 gold pieces.
The emblem of the Valiant Morgen Trading Company is a diamond in front of a red rising sun. It is portrayed in the stained glass window about the main entrance to the Valiant Morgen Trading Company Kaarst Branch.