A Massachusetts rarity, from the John Marshall collection from a one time find over 40 years ago, during the construction of I 495. Two large, complex pyrites to 4.4 CM are perched on a jumble of micro crystals mostly Magnetites with numerous Xenotime. The right side crystal is in perfect condition, the left shows an old stress crack that is partly rehealed. An exceptional example of this find, I have not seen any better ever. Displays well.