Capped column

From Glossary of Meteorology

capped column

A form of ice crystal consisting of a hexagonal column with plate crystals or stellar crystals at its ends and sometimes at intermediate positions.

The caps are perpendicular to the column and form as the crystal enters regions where change of air temperature leads to change in crystal structure from column to plate.

Copyright 2022 American Meteorological Society (AMS). For permission to reuse any portion of this work, please contact Any use of material in this work that is determined to be “fair use” under Section 107 of the U.S. Copyright Act (17 U.S. Code § 107) or that satisfies the conditions specified in Section 108 of the U.S.Copyright Act (17 USC § 108) does not require AMS’s permission. Republication, systematic reproduction, posting in electronic form, such as on a website or in a searchable database, or other uses of this material, except as exempted by the above statement, require written permission or a license from AMS. Additional details are provided in the AMS Copyright Policy statement.