Byne's disease

Byne's disease, more accurately known as Bynesian decay, is a peculiar and permanently damaging condition (resulting from an ongoing chemical reaction) which often attacks mollusk shells that are in storage or on display for long periods of time.

Bynesian decay is a form of efflorescence of salts formed by the reaction of acidic vapors with the basic shell surface. The efflorescence can sometimes superficially resemble a growth of mold. Although first described in the early 19th century, Bynesian decay was not well understood until almost a hundred years later. The condition is named after the man (L. Byne) who is best known for describing it in the late 19th century, even though he was not the first person to describe it in print. In addition, Byne mistakenly assumed that the condition was caused by bacteria, and thus the condition came to be referred to as a "disease".

In addition to mollusk shells, various other natural history specimens are susceptible to this form of decay, including eggshells and some fossils and mineral samples that are composed of calcium carbonate. This condition is of concern for museum scientists, and also for anyone who has a private collection of specimens of these kinds. In order to avoid Bynesian decay, the use of metal, non-reactive polymers and acid-free materials of archival quality are preferred over common paper, wood-based materials, ordinary glues and varnishes in collection environments. Management of affected specimens includes washing and thorough drying, with a subsequent realocation to an archival setting.

Byne's disease can appear as a powdery white coating on a shell. It also often looks as if a shell has been "infected" with mold; however, under magnification the mold-like appearance is revealed to be a crystalline growth of salts.

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