Klorastolite, Batu Mulia Berwarna Hijau Dari Kawasan Karangsambung, Kebumen, Jawa Tengah

The greenness rock with spotted white and light green mineral and gemstone quality has founded in Karangsambung area, near boundary between Banjarnegara and Kebumen Regency. Many outcrop and boulder samples associated with Luk Ulo Melange komplex have been collected from Lokidang river, Binangun, Kalitengah and Kebondalem. Samples from Lokidang river associated with ophiolite rocks while the sample from Binangun-Somagede and Kebondalem associated with metamorphic rocks; schists and gneiss. Petrographic analysis of gemstone from Kalitengah and Kebondalem, were characterized by tremolite-actinolite microcrystalin, microlite of feldspar or plagioclase, chlorite and opaque mineral, could be namelly as Nephrite. Mineralogy analysis, concoidal fracture, 6th – 7th Mohs hardness, greasy lustre, translucent, specific gravity 3.2 – 3.4 gr/cm 3. The siliceous rocks sample from Lokidang river was arranged by quartz with tremolite veinlets, chlorite and opaque minerals. However, based on spesific gravity data, the petrographic analysis become not convince, therefore it was continued with microprobe analysis, especially sample from Kebondalem. From this data, the greenish rock has published as javan jade was chlorastolite, characterized by dominantly pumpellyite mineral. Keywords : Karangsambung, greenish rock, javan jade, chlorastolite Jurnal Bahan Galian Industri, Volume 11, No 30, PPTMB, Bandung