This old label and specimen came to light the other day when we were moving some boxes around in the TVM store room.
Mineralhaus Droop was based in Dresden and this label has an uncertain age but likely to date from later in the period of 1905 -1930s.
The other interest in the specimen is the name Comptonit(e), this is a disused or old name for thomsonite-Ca, and Kaaden is the old locality name for Kadaň in Bohemia.
This does bring out a foible or even a conflict between collecting and mineralogical history in so much that the piece is historic and labelled correctly for the time, now of course is incorrect.
To deal with this e-Rocks uses a naming system that allows the old name to be listed, but links via "a renamed to" connection to the current name; hopefully to give the best of both worlds!
If you look at the item listed below and select the minerals tab it will show the connection.
You will also see the label image stored under the labels tab.