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fresh is pleochroic, varying from light brown to green. Accessory minerals include zircon, titaniteand allanite which is commonly altered.Age RelationsDie fine- to medium-grained granite is considered to be a textural variant of medium-grainedgranite exposed on Lantau Island and is, therefore, presumed to be of similar age. On Chek LapKok, the fine- to medium-grained granite probably cooled before the fine-grained granite exposedin the west of the island.m B 9:^ ^ r\ i -Plate 24 - Fine to Medium-grained Granite (11309 17165), from a Borehole South of Ha Law WanFine-grained GraniteDistribution andLithologyFine-grained granite within the district can be divided into megacrystic and non-megacrysticvarieties. The richly megacrystic varieties generally occur adjacent to, or within, gradationalcontact zones with porphyritic, fine- to medium-grained granite and porphyritic, medium-grainedgranite, whereas the non-megacrystic varieties generally occur as separate intrusive bodies.Megacrystic varieties may also occur as textural variants within feldsparphyric rhyolite dykes.Fine-grained granite in the district occurs mainly on Tsing Yi, in and around Ma Wan and thenorthern part of Lantau Island, in central Lantau Island, on Chek Lap Kok and at Sha Lo Wan.Smaller exposures are found on many of the offshore islands.