serpentine

serpentine¹

/serr"peuhn teen', -tuyn'/, adj., n., v., serpentined, serpentining.

adj.

1. of, characteristic of, or resembling a serpent, as in form or movement.

2. having a winding course, as a road; sinuous.

3. shrewd, wily, or cunning.

n.

4. a device on a harquebus lock for holding the match.

5. a cannon having any of various bore sizes, used from the 15th to the 17th century.

6. Skating. a school figure made by skating two figure eights that share one loop.

v.i.

7. to make or follow a winding course: The stream serpentines through the valley.

[1350-1400; ME (adj.) < L serpentinus snakelike, equiv. to serpent- SERPENT + -inus INE¹]

Syn. 2. twisting, snaking, tortuous.

serpentine²

/serr"peuhn teen', -tuyn'/, n.

a common mineral, hydrous magnesium silicate, H₂Mg₃Si₂O₂, usually oily green and sometimes spotted, occurring in many varieties: used for architectural and decorative purposes.

[1350-1400; ME serpentyn < ML serpentinum, n. use. of neut. of serpentinus SERPENTINE¹]

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Any of a group of magnesium-rich silicate minerals whose composition resembles Mg₃Si₂O₅(OH)₄.

Serpentine generally occurs in three forms: as chrysotile, the most common variety of asbestos; and as antigorite or lizardite, both of which are commonly massive and fine-grained. Named in allusion to its resemblance to a snake's skin, serpentine is usually grayish, white, or green but may be yellow or green-blue. It takes a high polish and is sometimes used as an ornamental stone.

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▪ mineral

      any of a group of hydrous magnesium-rich silicate minerals. The composition of these common rock-forming minerals approximates Mg₃Si₂O₅(OH)₄. Serpentine generally occurs in three polymorphs: chrysotile (q.v.), a fibrous variety used as asbestos; antigorite, a variety occurring in either corrugated plates or fibres; and lizardite, a very fine-grained, platy variety. Named in allusion to its resemblance to a snake's skin, serpentine is usually grayish, white, or green but may be yellow (chrysotile) or green-blue (antigorite); the green colour is due to iron replacing magnesium.

      Serpentine is formed below 500° C (930° F) by the addition of water and sometimes silica to various magnesium silicates, e.g., forsterite or enstatite. It characteristically occurs along the crests and axes of great folds, such as island arcs or Alpine mountain chains. Typical occurrences are in altered peridotites, dunites, or pyroxenites; serpentinite is a rock consisting largely of serpentine. Serpentine takes a high polish and is sometimes used as an ornamental stone.

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