Forwarded for Bas, who has chenged his ISP and
has yet to sort it out with the listserve.

>X-Sieve: CMU Sieve 2.2
>From: "Rosemary Payne" <[log in to unmask]>



>Dear Linda:
>
>Close control of temperature and humidity probably aren't that important for
>most shell collectors, and other things are probably more important.
>
>The shells themselves need to be in reasonable condition for storage.  In
>particular, any remaining bits of the animal - small parts left inside
>gastropods, or pieces of muscles, need to be removed or to have time to dry
>out fully before being stored, especially in closed containers, and marine
>shells should have been soaked in fresh water and rinsed to remove most of
>the salt.
>
>Labels, bags, boxes and cabinets need to be made of stable materials - and,
>especially, not of materials that contain acid residues or produce acid
>break-down products over time.   Paper labels and cardboard boxes should be
>acid-free or low-acid, especially if they come in direct contact with the
>shells.  Polythene bags are fine, as are most hard clear plastics; but
>beware PVC, or plastic with added plasticisers.  Be cautious of wood -
>especially oak; and be doubly cautious of most wood products (for instance
>hardboard, chipboard, particle board and MDF - they may have other names in
>the US), which tend to emit acids from the chemicals used to glue them
>together.
>
>Prolonged exposure to direct light and UV light  should be avoided.
>
>The recommendations you're likely to get from museum conservation
>professionals about humidity and temperature are often more demanding than
>most shells need.  It's probably enough for most purposes and in most
>situations to keep humidity between 35% and 75% and temperature between 5oC
>and 30oC.  Of the two the two, humidity is more important because above
>70-80% fungal and other microbiological attack are likely, while below
>30-40% periostraca dry and crack quite quickly.  It's also desirable to
>avoid rapid change, and especially repeated rapid change.
>
>In many places and climates, most inhabited buildings provide reasonable
>conditions if you keep your shells away from windows and from external
>walls, and inside cupboards or boxes made of suitable materials, which
>moderate the effect of fluctuating conditions.  It's often not too hard to
>protect from conditions outside these broad limits without too much expense.
>In the UK, where I live, high humidity, low temperature and UV light are
>probably the main problems.  I keep much of my collection in a loft over an
>unheated outside garage.  Blinds on the windows cut out light and UV
>radiation; insulating the roof has reduced temperature variation.  A small
>electric heater with a crude temperature sensor provides enough heat when
>the temperature falls below around 8oC, and a small dehumidifier cuts in a
>removes humidity when this goes above about 70%.  The blinds, heater and
>dehumidifier together cost around £130 ($200);  annual running costs are not
>high (and I keep lots of other things in the loft!).   Very close control
>isn't needed, and costs a great deal;  what's important is simply to think
>about all the possible causes of damage, and keep them within reasonable
>limits.
>
>Best wishes,
>
>Bas Payne