M, I'll ride with Trav, that top point might need a real professional opinion. Like at a flint show where
non binding opinions are free.
The scale on flint can accumulate in as little as 300 yrs depending on soil conditions. It's reccomended to leave any residue on at least until it is professionally examined ( or forever ).
If you prefer clean, 9% vinegar will do it without damage.
Second point may never be known for sure with so much missing. A good appraiser might offer a few possibilities based on overall design and flaking