A trunk containing about 2,600 undelivered letters—600 of them unopened — was recently rediscovered. A team of researchers is now collaborating on a new project to study the rare archive, using X-rays to virtually open the sealed notes. (All images ©Signed, Sealed & Undelivered Team, 2015. Courtesy of the Museum voor Communicatie, The Hague) [Read full story about the initiative to study the sealed letters]

Fancy monograms

Researchers are examining a trove of unopened 17th-century letters. The initiative, dubbed "Signed, Sealed & Undelivered," aims to virtually open and inspect the historic notes. This letter features a red wax seal.


Rich and decorative seals

A letter with a gold wax seal.


Open for all to see

An unfolded letter from the 17th century.


An elegant marking

Some of the letters are sealed with insignias embedded into the paper.


Detailed crest

The paper seals offer details and information about the letter's origin and destination.


Sneak peek

A partially opened letter.


Unrequited love

The researchers said this letter contains a refused love letter.


Official insignia

The trunk belonged to a 17th-century postmaster, and had been sitting undisturbed in The Hague's Museum voor Communicatie since 1926.


Unique fastenings

In examining the unopened 17th-century letters, unique facets were found, such as this paper lock.


Letters to the unknown

Another letter seems to have been opened, perhaps in hopes of locating the recipient.


A touch of color

A few of the letters included decorated, colorful enclosures such as this paper dove, which represents the Holy Spirit, with the inscription "don de piété," which means gift of piety.


Fancy folds

This letter has been folded into a diamond shape.


Ragged messages

Example of a letter that was torn when it was opened.


X-ray tech

Using the latest advances in X-ray technology from the field of dentistry, the researchers will scan the sealed letters without opening them. This screenshot shows a slice of a packet of 20 stacked letters.


Burned beauty

This letter was burned and needs treatment from a conservation expert before it can be scanned.


A unique collection

The trunk in which the undelivered letters were kept.


A beautiful practice

The almost-forgotten practice of writing letters was an art in and of itself: the script, the wax and paper seals, the detailed foldings, enclosures and even paper locks.

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