page_title: Seashell surface
hierarchical_section_title: Seashell surface
caption_attribution_description: Astralium calcar (Linné, 1758) Deutsch: Durchmesser 3,5 cm; Herkunft: Philippinen. English: Wheel-like Star Shell , Diameter 3.5 cm; Originating from the Philippines; Shell of own collection, therefore not geocoded. Français&#160;: Coquille d'Astralium calcar, pêchée dans les Philippines. Longueur 3,5&#160;cm.
context_page_description: In mathematics, a seashell surface is a surface made by a circle which spirals up the z-axis while decreasing its own radius and distance from the z-axis. Not all seashell surfaces describe actual seashells found in nature.
context_section_description: In mathematics, a seashell surface is a surface made by a circle which spirals up the z-axis while decreasing its own radius and distance from the z-axis.  Not all seashell surfaces describe actual seashells found in nature.
caption: Wheel-like Star Shell Astralium calcar, Diameter 3,5 cm; Originating from the Philippines
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