chalcedony
chalcedony[kalˈsɛdəni](pl. -ies)- [mass noun]a microcrystalline type of quartz occurring in several different forms including onyx and agate
玉髓
派生chalcedonic[ˌkalsɪˈdɒnɪk]adjective语源- late Middle English: from Latin calcedonius, chalcedonius (often believed to mean 'stone of Chalcedon', but this is doubtful), from Greek khalkēdōn
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