[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: SV: "carbonatic" eggshell query

Thanks. Tommy.
Composition may not be the key, as I am finding out.
Maybe thickness is.

David Peters
St. Louis

On Sep 27, 2009, at 2:34 PM, Tommy Tyrberg wrote:

As far as I know at least all bird eggshells are largely "carbonatic" in the sense that they are mostly Calcium Carbonate (there is also a small proportion of organic material, and some also contain a small amount of Calcium Phosphate). In so far as pterosaurs had hard eggs I imagine they
would be similar.
Soft eggs (often described as "leathery") have membraneous shells that
are a mixture of organics (mostly proteins) and calcium carbonate. The
carbonate may be either a thin continuous layer or nodular.

Timmy Tyrberg

-----Ursprungligt meddelande-----
Från: owner-DINOSAUR@usc.edu [mailto:owner-DINOSAUR@usc.edu] För David
Skickat: den 27 september 2009 16:58
Till: dinosaur mailing list
Ämne: "carbonatic" eggshell query

Chiappe et al. 2004 described the Pterodaustro eggshell as
"carbonatic" . A Google query listing "eggshell" and "carbonatic"
listed only the Chiappe et al. article.

What does "carbonatic" mean in terms of eggshells? What is this like?
What is this not like?

David Peters
St. Louis