Lead Seal: History, Use, Recycling and Manufacturing
The lead seal is a security device used since Antiquity to guarantee the integrity of a container, a document or a shipment. First appearing in Roman times, it was employed to seal grain sacks, official correspondence or merchandise, bearing a mark specific to an authority, administration or merchant. Its primary purpose was to detect any attempt at fraudulent tampering.
History and Use of Lead Seals
For centuries, lead has been favored for its malleability, corrosion resistance, and the ease with which a seal could be stamped into it. The seal combined with a metal wire or string is closed by crimping it with a sealing plier — a process that involves mechanically compressing the lead around the wire to create a tamper-proof closure.
Manufacturing and Expertise at Dejoie-Lemer
Since 1929, we have specialized in the manufacturing of security seals made of lead and other materials. Our seals have been supplied to customs authorities, rail networks, and various industries. Since joining the Lemer Group in 1989, we have continued producing lead seals at our historical site in Carquefou, where traditional know-how meets modern industrial techniques.
Natural and express lead seals are produced through molding or injection with high precision (often with a tolerance below 0.1 mm). Each unit is carefully checked to ensure consistency and mechanical strength, meeting the highest industry standards.
Recycling, Sustainability and Lead-Free Alternatives
The raw material we use is sourced primarily from recycled car batteries, making our seals particularly environmentally friendly. This approach reduces the need for raw material extraction and significantly lowers the carbon footprint of our production process.
In addition, our technical expertise in low-melting-point alloys allows us to also manufacture products in tin (lead-free), fully compliant with RoHS (Restriction of Hazardous Substances) and REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) standards. These alternatives offer the same level of security while meeting the most stringent environmental and health regulations.
