Formic acid formulations and properties:
- Available as 5%–10% aqueous, 25% formic with sodium citrate, 4% formic with 4% HCl
- Most common decalcifier
- Slower acting
- Good staining results
- Economical
- Staining acceptable after prolonged exposure
- Formic acid and formaldehyde are a common fixative/decal combination
