I value detailed locality data as much as the next guy.  It makes a
collection much more interesting, and adds scientific value as well.
However, obtaining such data is often not possible.  Many of the shells
obtained from retail dealers come to them from foreign suppliers who run
fairly substantial export operations.  These wholesale exporters typically
do not personally go out dredging or diving for the shells they sell.  They
purchase them from smaller wholesalers.  Here is an example of how it might
work - In a fishing village, some enterprising individual may make the
rounds of the local fishermen, purchasing whatever they bring in.  Perhaps
each fisherman drops off a box of shells at his house.  He doesn't keep each
fisherman's catch separate - he pools the shells, perhaps separating them by
species, perhaps not.  In one of the area villages there may be an
individual who runs a larger operation. He has a small warehouse of some
kind, and weekly he makes the rounds of the local villages, buying what each
local entrepreneur has amassed.  He takes the shells back to his place and
sorts them, probably paying some attention to different degrees of quality.
He doesn't keep track of which village each shell came from - he pools
specimens of similar species and quality.  Somewhere on the island, if it is
a large one, or on a nearby island, there is probably a still larger
operation which buys from the smaller sellers in the area.  Such an
operation may deal in specimen shells and commercial shells, and sorts
incoming shells into those categories, as well as by species and quality -
but not by collection locality.  Finally, there are a number of
knowledgeable, well organized, upper end wholesale specimen shell dealers,
who make regular buying trips to the major centers, and hand-pick the best
quality material.  I deal with a few such individuals.  Every few months
they fly to Samar, Bohol, Cebu, Palawan, and various other areas.  At least
one owns his own plane.  There, they may look over 200 Angaria vicdani, and
pick out the best 10 or 20.  As a result of this system, they can regularly
send me truly spectacular specimens.  The 200 specimens they selected from
have already been culled several times, so the shells they bring home may
truly be "one in a thousand" specimens.  But, also because of this system,
the specimens are accompanied only by basic data.  These are some of the
best suppliers in the business, but they can't provide what they cannot
obtain.  By the time they make their purchases, the shells have changed
hands several times; they have been pooled and split several times; and
there is simply no way to know exactly where any given specimen came from.

Another consideration is the probable accuracy of the data provided.  One
time I was receiving nice deep water shells from a wholesaler in Taiwan.  He
provided only very basic data - something like "S.W. Taiwan, 40 fathoms".
Naturally, I would have preferred more complete data, so I came up with an
idea.  I sent him blank data slips, listing the information I would like,
and asked him to just fill in the blanks for each lot of shells he sent me.
I was buying enough from him that he was willing to take the trouble, and
all of a sudden I had nice, detailed locality data - specific location,
bottom type, etc. -  which I passed along to customers.  About a year later
I heard another dealer complaining about the very limited data this supplier
provided.  Then the wheels started turning.  I figured (1) if this supplier
had ready access to such data, why didn't he send it to me from the
beginning; (2) if he didn't have access to the data back then, how did he
suddenly come up with such data when I pressured him for it; and (3) if he
now has such data available, why is he sending it only to me, and not to
other customers?  I finally figured he was just telling me what I wanted to
hear.  If making the sale meant taking a minute to write something on a slip
of paper, he was willing to do that.  It only takes a minute to make up
something believable.  So, sadly I had to conclude that pressuring suppliers
for data that they don't have is likely to result in fabrication of data,
just to make the sale.  They either have to say "I don't have the kind of
data you want, so I can't sell to you", or the obvious alternative.  I would
rather have basic data that is accurate than detailed data that is
fictitious.  So, now I let them know I prefer good data, but I try not to
make it sound like an ultimatum, and then in the end, I take what I get for
data, figuring that is the best they can supply, and I concentrate on the
quality of the specimens.

I also deal with many smaller suppliers  who actually do collect the
specimens they sell, or at least get them directly from the fishing boats.
Such folks are usually quite willing to supply very detailed collection
data, and in these cases I am confident the data is accurate.  In most other
cases, I am not.

Regards,
Paul M.