Every common mistake has a physical or chemical reason behind it. Let’s decode the “why,” so you can spot trouble before it starts.
10) SKIPPING PERMISSION
Legal and ethical risk aside, caretakers often know which stones are fragile or slated for professional repair. Permission = information.
9) NO BASELINE DOCUMENTATION
Without before‑photos, you can’t verify change. Use consistent angles and exposure; add brief condition notes (cracks, sugaring, delamination).
8) EXTREME WEATHER CLEANING
Freeze‑thaw: water expands ~9% on freezing; trapped moisture can wedge grains apart. In hot, direct sun, solutions flash‑dry and leave residues. Choose mild windows.
7) HOUSEHOLD CHEMICALS
Bleach leaves chloride salts; vinegar/acid dissolves calcite and can mobilize salts. Short‑term “bright,” long‑term loss. Conservation asks, “Is this reversible?”—household chemicals rarely are.
6) ABRASIVE TOOLS
Wire brushes cut mineral grains; iron residues can rust. Use soft, flagged bristles; let time and water lift soils.
5) INADEQUATE RINSE
Residues wick back into pores and crystallize. Rinse until runoff is clear; edges and lettering, too.
4) IGNORING ERGONOMICS & SAFETY
Fatigue → sloppy technique. Gloves, eye protection, hydration, and body mechanics prevent mistakes (and injuries).
3) DIY STRUCTURAL REPAIRS
Incompatible mortars/adhesives trap moisture and are not reversible. Cleaning is one thing; structural work is its own discipline—get trained or refer out.
2) SOLO KNOWLEDGE
Tap the community and literature; you’ll inherit 50 years of experiments you don’t need to repeat the hard way.
1) CHASING “LIKE‑NEW”
Our goal: legibility and stone health, not bleach‑white perfection. Over‑cleaning thins inscriptions and opens pores. Stop when your objective is met.
FIELD RULE: IF YOU CAN’T UNDO IT, THINK TWICE
Reversibility is a conservation north star. If a method can’t be undone, it better be gentle, proven, and necessary.
