Please use this identifier to cite or link to this item:

Mineralogical Variation in Shells of the Blackfoot Abalone, Haliotis iris (Mollusca: Gastropoda: Haliotidae), in Southern New Zealand

File Size Format  
vol58n1-47-64.pdf 2.02 MB Adobe PDF View/Open

Item Summary

Title:Mineralogical Variation in Shells of the Blackfoot Abalone, Haliotis iris (Mollusca: Gastropoda: Haliotidae), in Southern New Zealand
Authors:Gray, Blair E.
Smith, Abigail M.
Date Issued:Jan 2004
Publisher:University of Hawai'i Press
Citation:Gray BE, Smith AM. 2004. Mineralogical variation in shells of the blackfoot abalone, Haliotis iris (Mollusca: Gastropoda: Haliotidae), in southern New Zealand. Pac Sci 58(1): 47-64.
Abstract:The New Zealand blackfoot abalone, Haliotis iris Gmelin, is among
the few gastropods that precipitate both calcite and aragonite in their shells. The
location, composition, and thickness of these mineral layers may affect color,
luster, and strength of the shell, which is locally important in jewelry manufacture.
Skeletal mineralogy and shell structure of H. iris from three southern
New Zealand locations were determined using X-ray diffractometry, scanning
electron micrography, and mineral staining. In H. iris an outer calcitic layer is
separated from an inner aragonitic surface by both calcified and noncalcified
organic layers running longitudinally through the shell. Skeletal mineralogy
within individual shells varies from 29 to 98% aragonite, with older shell having
significantly higher aragonite content than young sections. Variation within
populations ranges from 40 to 98% aragonite, and among three populations
from 34 to 98% aragonite. Shell thickness, too, varies within individual shells
from 0.2 to 4.2 mm, with a significant positive relationship with age. Within population
variation in shell thickness ranges from 2.1 to 5.4 mm, with no
significant difference in shell thickness variation among populations. The high
degree of variability within and among individual shells suggests that it is
essential to test replicate samples from individual mollusk shells, especially when
they have complex bimineral structure.
Appears in Collections: Pacific Science Volume 58, Number 1, 2004

Please email if you need this content in ADA-compliant format.

Items in ScholarSpace are protected by copyright, with all rights reserved, unless otherwise indicated.