Bird's eye maple


Bird's eye maple

Bird's eye maple is a specific type of extinction exhibited by micas, especially muscovite under cross polarized light. It gives the mineral a pebbly appearance as it passes into extinction. This is caused when the grinding tools used to create petrographic slides of precise widths alter the alignment of the previously perfect basal cleavage planes which split micas up into its characteristic thin sheets. The resulting, slightly roughened surface alters the extinction angle of various parts of the crystal lattice, leading to this type of extinction. Since it is not a natural feature of the mineral, bird's eye maple is not observed in all mica crystals, nor from all angles, but it is quite common, and is used as a diagnostic feature for micas.


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  • Bird's-eye maple — Maple Ma ple (m[=a] p l), n. [AS. mapolder, mapulder, mapol; akin to Icel. m[ o]purr; cf. OHG. mazzaltra, mazzoltra, G. massholder.] (Bot.) A tree of the genus {Acer}, including about fifty species. {Acer saccharinum} is the {rock maple}, or… …   The Collaborative International Dictionary of English

  • Bird's-eye maple — Bird s eye ma ple See under {Maple}. [1913 Webster] …   The Collaborative International Dictionary of English

  • bird's-eye maple — bird s′ eye ma′ple n. bui fun a cut of sugar maple wood having a wavy grain with many dark, circular markings • Etymology: 1785–95 …   From formal English to slang

  • bird's-eye maple — noun maple wood having a wavy grain with eyelike markings • Hypernyms: ↑maple …   Useful english dictionary

  • bird's-eye maple — noun Date: 1793 wood of the sugar maple having a wavy grain that causes markings resembling eyes …   New Collegiate Dictionary

  • bird's-eye maple — a cut of sugar maple wood used esp. for veneers, having a wavy grain with many dark, circular markings. [1785 95] * * * …   Universalium

  • Bird's-eye — a. 1. Seen from above, as if by a flying bird; embraced at a glance; hence, general; not minute, or entering into details; as, a bird s eye view. [1913 Webster] 2. Marked with spots resembling bird s eyes; as, bird s eye diaper; bird s eye maple …   The Collaborative International Dictionary of English

  • bird's-eye — /ˈbɜdz aɪ / (say berdz uy) adjective 1. seen from above: a bird s eye look at the new sub division. 2. general; not detailed: a bird s eye history of music. 3. having spots or markings resembling birds eyes: bird s eye maple. –noun 4. a type of… …   Australian English dictionary

  • Maple — Ma ple (m[=a] p l), n. [AS. mapolder, mapulder, mapol; akin to Icel. m[ o]purr; cf. OHG. mazzaltra, mazzoltra, G. massholder.] (Bot.) A tree of the genus {Acer}, including about fifty species. {Acer saccharinum} is the {rock maple}, or {sugar… …   The Collaborative International Dictionary of English

  • Maple honey — Maple Ma ple (m[=a] p l), n. [AS. mapolder, mapulder, mapol; akin to Icel. m[ o]purr; cf. OHG. mazzaltra, mazzoltra, G. massholder.] (Bot.) A tree of the genus {Acer}, including about fifty species. {Acer saccharinum} is the {rock maple}, or… …   The Collaborative International Dictionary of English