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Crystal morphologies in whewellite stones: electron microscopy
Investigative Urology
|November 1, 1981
Summary
Whewellite stones, composed of organic and inorganic phases, were studied using advanced microscopy. Researchers found that an amorphous organic matrix is sandwiched between crystalline whewellite, likely responsible for stone cohesion.
Area of Science:
- Geochemistry
- Materials Science
- Biomineralization
Background:
- Whewellite (calcium oxalate monohydrate) is a common mineral found in various geological and biological contexts, including urinary and kidney stones.
- Understanding the microstructural organization of whewellite is crucial for elucidating its formation mechanisms and properties.
Purpose of the Study:
- To investigate the spatial distribution and relationship between the organic matrix and crystalline phases in whewellite stones.
- To determine the role of the organic matrix in the structural integrity and cohesion of whewellite stones.
Main Methods:
- Examination of both dried and freshly extracted whewellite stone samples.
- Utilized light microscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM).
- Employed phase contrast and dark field TEM imaging techniques for high-resolution analysis.
Main Results:
- Crystalline whewellite phases were observed in oriented clusters with parallel-stacked crystals.
- Transmission electron microscopy revealed distinct gaps, approximately 100 Angstroms, between crystals.
- Dark field TEM imaging indicated that these intercrystalline gaps are filled with the amorphous organic phase.
Conclusions:
- The amorphous organic matrix is spatially located between the crystalline whewellite phases.
- This matrix likely acts as a binding agent, contributing significantly to the cohesion and structural stability of whewellite stones.
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