Twinnite is a very rare sulfosalt which is the material with the shiny, metallic luster. The yellow material is very likely Wakabayashilite which is often associated with Twinnite at this location (however there are at least two other yellow colored species also found at the location).
Condition: Fairly Good
Flaws: Essentailly massive material. There are some cracks in the matrix.
This mineral is also found in the following galleries: Minerals From Europe | Sulfides and Sulfosalts | Rare Minerals | Minerals Priced Between 50 and 99 Dollars