I think it's the ziplock bags.  I use indelible ink on small squares of plastic cut from heavy gauge
disposable plastic plates.  Haven't stored this way for more than a few months, but no fading yet.

Alan Gettleman wrote:

> Hello,
> Hopefully a simple question to answer.  When collecting in the field I
> place shells in zip lock bags pending cleaning, and use a 'permanent
> marker' to annotate location number.  These numbers on the bags often
> faded, so I used the same marker to note the number on a slip of paper
> and put that into a small ziplok bag and insert into the larger bag.
> Often any moisture getting into the small bags also faded those
> numbers.  I know museums have written labels that are always in liquid
> in their 'wet' collections.  What kind of marker, what kind of paper
> (that you can easily obtain and is easy to use in the field)?
>
> Thanks.
>
> Alan Gettleman
> Merritt Island, FL

--
Marlo
Merritt Island, Florida
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