When clients ask which medium we prefer, we answer with questions about their storage room rather than pronouncements about durability. Paper and steel fail differently, and our logbooks record those differences in separate columns.

Paper backups

Laminated seed cards resist spills but not prolonged humidity above 65%. Ink can ghost through lamination if stored face-to-face under pressure. Re-sealing after inspection requires new envelopes and tape—plan for that in your log’s supply section.

Steel backups

Engraved plates and stamped capsules tolerate humidity swings but corrode near unvented bathrooms or chemical closets. Capsule lids need torque-consistent closing; we photograph thread alignment because cross-threading mimics tampering in later comparisons.

Our recommendation

Maintain one primary medium and one secondary of the opposite type. Log them on facing pages so future readers understand which copy is authoritative for re-sealing procedures. Never assume steel eliminates the need for environmental notes—condensation forms inside capsules left in exterior walls during winter.