Sort ACT items by age and type

[baskaufs]

In anticipation of adding based_on statements, we need to know which works are over 100 years old (or pre-1800). It would also be useful to sort them out by type (typical artwork types like painting and mosaic, vs. others like photographs or buildings).

Charlotte is going to ask Jodie to do another export of the whole database so that we can work on this (and other things) using the most up to date data.

[baskaufs]

This export was apparently done as https://github.com/HeardLibrary/vandycite/blob/master/act/processed_lists/clean_metadata_2022-09-29.csv