Penny Higgins wrote:

> Just for curiosity, did you change cap colors? 
 > It's bizarre, but I don't think I'm
> the only one who's ever noted this.

> I, for one, don't trust the white caps. I only use them for testing. 
> Blue caps are OK most of the time. Green caps work the best for us. I 
> don't think I've ever had a green cap leak. I haven't tried any other 
> colors - but I need to order some more soon. I think I'll go with green.

We tested white, blue and brown (brown were on sale for half price; now 
I know why...).

The blue caps worked fine with the flat bottom soda vials for 18O water 
analysis and fit more or less (push it!) on the round bottom 
borosilicate vials (old and new thread). For the flat vials we stay with 
the blue caps.

The brown caps did not fit at all, but once the cap made it on the vial 
(push it harder!) they did not leak. In contrast to Penny the white caps 
seems to fit very good on the new thread boro vials (and can also be 
used on the flat vials). We haven't tested the green ones, however...

regards,
Robert

-- 
Dr. Robert van Geldern
Section 3: Geochronology and Isotope Hydrology
Leibniz Institute for Applied Geosciences (GGA-Institute)

GEOZENTRUM HANNOVER
Stilleweg 2
30655 Hannover, Germany

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