霞(xia)石(shi)(shi)(shi)正長(chang)(chang)巖 nepheline-syenite 一種深成堿(jian)(jian)(jian)性(xing)(xing)巖。灰、淺(qian)綠(lv)、淺(qian)黃褐色(se)。中粗粒。具似(si)花崗結構(gou)。主(zhu)要(yao)由堿(jian)(jian)(jian)性(xing)(xing)長(chang)(chang)石(shi)(shi)(shi)(65%～70%)、霞(xia)石(shi)(shi)(shi)(15%～25%)和(he)堿(jian)(jian)(jian)性(xing)(xing)暗色(se)礦物(wu)(10%～15%)組成。堿(jian)(jian)(jian)性(xing)(xing)長(chang)(chang)石(shi)(shi)(shi)主(zhu)要(yao)為(wei)正長(chang)(chang)石(shi)(shi)(shi)、歪長(chang)(chang)石(shi)(shi)(shi)、微斜長(chang)(chang)石(shi)(shi)(shi)和(he)鈉長(chang)(chang)石(shi)(shi)(shi);堿(jian)(jian)(jian)性(xing)(xing)暗色(se)礦物(wu)以(yi)霓(ni)輝石(shi)(shi)(shi)、霓(ni)石(shi)(shi)(shi)、鈉鐵(tie)閃石(shi)(shi)(shi)、富(fu)鐵(tie)鈉閃石(shi)(shi)(shi)為(wei)主(zhu)。輝石(shi)(shi)(shi)類(lei)礦物(wu)的環帶構(gou)造發育。

　　常見磁鐵礦、鈦鐵礦、磷灰石(shi)(shi)(shi)、鋯石(shi)(shi)(shi)、榍石(shi)(shi)(shi)等副礦物。主要(yao)(yao)巖(yan)(yan)石(shi)(shi)(shi)變種(zhong)有(you)(you)：①云(yun)(yun)霞(xia)(xia)正(zheng)長(chang)(chang)(chang)巖(yan)(yan)。主要(yao)(yao)由鉀長(chang)(chang)(chang)石(shi)(shi)(shi)、鈉長(chang)(chang)(chang)石(shi)(shi)(shi)、霞(xia)(xia)石(shi)(shi)(shi)和鐵黑云(yun)(yun)母(mu)組(zu)成。②流(liu)霞(xia)(xia)正(zheng)長(chang)(chang)(chang)巖(yan)(yan)。主要(yao)(yao)由正(zheng)長(chang)(chang)(chang)石(shi)(shi)(shi)(57%)、霞(xia)(xia)石(shi)(shi)(shi)(20%～25%)、霓石(shi)(shi)(shi)、輝(hui)石(shi)(shi)(shi)、角閃石(shi)(shi)(shi)及(ji)少(shao)(shao)量黑云(yun)(yun)母(mu)、鈉長(chang)(chang)(chang)石(shi)(shi)(shi)組(zu)成。③鈉霞(xia)(xia)正(zheng)長(chang)(chang)(chang)巖(yan)(yan)。其(qi)主要(yao)(yao)特征是其(qi)中的(de)長(chang)(chang)(chang)石(shi)(shi)(shi)均為鈉長(chang)(chang)(chang)石(shi)(shi)(shi)。典型的(de)鈉霞(xia)(xia)正(zheng)長(chang)(chang)(chang)巖(yan)(yan)由板狀霞(xia)(xia)石(shi)(shi)(shi)(15%～30%)、長(chang)(chang)(chang)柱狀鈉長(chang)(chang)(chang)石(shi)(shi)(shi)(50%～70%)及(ji)少(shao)(shao)量暗色礦物組(zu)成。在(zai)自然(ran)界，多呈巖(yan)(yan)床、巖(yan)(yan)株產出。常與(yu)堿性(xing)正(zheng)長(chang)(chang)(chang)巖(yan)(yan)、堿性(xing)花崗巖(yan)(yan)、堿性(xing)輝(hui)長(chang)(chang)(chang)巖(yan)(yan)等一起(qi)組(zu)成雜巖(yan)(yan)體(ti)。與(yu)其(qi)有(you)(you)關的(de)礦產有(you)(you)鈮、鉭、稀土、鋯和鈾等。

　　堿性巖(yan)中(zhong)最重要的成(cheng)員。中(zhong)、粗粒，淺色(se)(se)，常具淺灰、綠(lv)、紅、黃(huang)色(se)(se)調(diao)。首(shou)次在烏(wu)拉爾被發現，曾被描述為(wei)“花崗巖(yan)，其中(zhong)石(shi)(shi)英為(wei)脂光(guang)石(shi)(shi)所代替”。巖(yan)石(shi)(shi)平均(jun)礦物成(cheng)分(fen)為(wei)：長石(shi)(shi)65～70%,霞石(shi)(shi)20%,暗(an)(an)色(se)(se)礦物10～15%。在某(mou)些類型中(zhong)暗(an)(an)色(se)(se)礦物可達20～25%，有時(shi)更多。

　　霞(xia)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)常(chang)(chang)與長(chang)(chang)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)交生(sheng)形成(cheng)微文象(xiang)結構(gou)。霞(xia)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)常(chang)(chang)被鈣霞(xia)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)、沸石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)類(lei)礦(kuang)物、絹云(yun)母等(deng)交代。堿性長(chang)(chang)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)主(zhu)要為(wei)正長(chang)(chang)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)、歪長(chang)(chang)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)、微斜長(chang)(chang)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)和(he)鈉(na)長(chang)(chang)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi);時(shi)有(you)條紋長(chang)(chang)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)。輝(hui)(hui)(hui)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)類(lei)礦(kuang)物以(yi)霓(ni)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)、霓(ni)輝(hui)(hui)(hui)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)為(wei)主(zhu)，透(tou)輝(hui)(hui)(hui)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)及鈦輝(hui)(hui)(hui)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)少見。輝(hui)(hui)(hui)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)斑晶環(huan)帶構(gou)造發育，往往自中(zhong)心向外為(wei)透(tou)輝(hui)(hui)(hui)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)、霓(ni)輝(hui)(hui)(hui)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)、霓(ni)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)。基質中(zhong)的(de)霓(ni)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)常(chang)(chang)呈針狀(zhuang)。鈦輝(hui)(hui)(hui)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)為(wei)紫(zi)色(se)，常(chang)(chang)構(gou)成(cheng)霓(ni)輝(hui)(hui)(hui)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)或透(tou)輝(hui)(hui)(hui)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)的(de)環(huan)邊(bian)。角(jiao)閃(shan)(shan)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)以(yi)鈉(na)鐵(tie)閃(shan)(shan)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)、富鐵(tie)鈉(na)閃(shan)(shan)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)為(wei)主(zhu)，鈉(na)閃(shan)(shan)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)、棕閃(shan)(shan)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)次之，有(you)時(shi)出現少量普通角(jiao)閃(shan)(shan)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)。云(yun)母主(zhu)要為(wei)金褐色(se)鐵(tie)黑云(yun)母，時(shi)常(chang)(chang)生(sheng)長(chang)(chang)在輝(hui)(hui)(hui)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)類(lei)及角(jiao)閃(shan)(shan)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)類(lei)礦(kuang)物的(de)外圍。最常(chang)(chang)見的(de)副礦(kuang)物為(wei)磁鐵(tie)礦(kuang)、鈦鐵(tie)礦(kuang)、磷灰石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)、鋯(gao)石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)和(he)榍石(shi)(shi)(shi)(shi)(shi)(shi)(shi)(shi)。

　　常(chang)見結(jie)構(gou)(gou)(gou)為似粗面(mian)結(jie)構(gou)(gou)(gou)和(he)(he)似花崗結(jie)構(gou)(gou)(gou)。有(you)時出(chu)現(xian)似片麻狀(zhuang)構(gou)(gou)(gou)造。根據(ju)礦(kuang)(kuang)物(wu)成(cheng)分(fen)和(he)(he)結(jie)構(gou)(gou)(gou)、構(gou)(gou)(gou)造特(te)點，霞(xia)(xia)(xia)石(shi)(shi)正(zheng)(zheng)(zheng)長(chang)(chang)(chang)(chang)(chang)(chang)巖(yan)(yan)可劃分(fen)出(chu)一些變種。①云霞(xia)(xia)(xia)正(zheng)(zheng)(zheng)長(chang)(chang)(chang)(chang)(chang)(chang)巖(yan)(yan)，其(qi)平均礦(kuang)(kuang)物(wu)成(cheng)分(fen)為:鉀長(chang)(chang)(chang)(chang)(chang)(chang)石(shi)(shi)30～40%,鈉(na)(na)(na)長(chang)(chang)(chang)(chang)(chang)(chang)石(shi)(shi)30～40%,霞(xia)(xia)(xia)石(shi)(shi)20%,鐵(tie)黑(hei)云母 5～10%。具它形粒狀(zhuang)結(jie)構(gou)(gou)(gou)、似片麻狀(zhuang)結(jie)構(gou)(gou)(gou)等。②流霞(xia)(xia)(xia)正(zheng)(zheng)(zheng)長(chang)(chang)(chang)(chang)(chang)(chang)巖(yan)(yan)，其(qi)礦(kuang)(kuang)物(wu)成(cheng)分(fen)為：正(zheng)(zheng)(zheng)長(chang)(chang)(chang)(chang)(chang)(chang)石(shi)(shi)57%和(he)(he)少量(liang)鈉(na)(na)(na)長(chang)(chang)(chang)(chang)(chang)(chang)石(shi)(shi)，霞(xia)(xia)(xia)石(shi)(shi)20～25%，霓(ni)石(shi)(shi)、輝石(shi)(shi)、角(jiao)閃石(shi)(shi)7%,少量(liang)黑(hei)云母。具半自形粒狀(zhuang)結(jie)構(gou)(gou)(gou)和(he)(he)似粗面(mian)狀(zhuang)結(jie)構(gou)(gou)(gou)。③鈉(na)(na)(na)霞(xia)(xia)(xia)正(zheng)(zheng)(zheng)長(chang)(chang)(chang)(chang)(chang)(chang)巖(yan)(yan)，其(qi)主要特(te)征是其(qi)中(zhong)的(de)長(chang)(chang)(chang)(chang)(chang)(chang)石(shi)(shi)均為鈉(na)(na)(na)長(chang)(chang)(chang)(chang)(chang)(chang)石(shi)(shi)。標型的(de)鈉(na)(na)(na)霞(xia)(xia)(xia)正(zheng)(zheng)(zheng)長(chang)(chang)(chang)(chang)(chang)(chang)巖(yan)(yan)由(you)板(ban)狀(zhuang)霞(xia)(xia)(xia)石(shi)(shi)(15～30%)、長(chang)(chang)(chang)(chang)(chang)(chang)柱狀(zhuang)自形鈉(na)(na)(na)長(chang)(chang)(chang)(chang)(chang)(chang)石(shi)(shi)(50～70%)及少量(liang)暗色礦(kuang)(kuang)物(wu)(霓(ni)石(shi)(shi)、鐵(tie)黑(hei)云母、角(jiao)閃石(shi)(shi)等)組成(cheng)。此外尚有(you)異(yi)性霞(xia)(xia)(xia)石(shi)(shi)正(zheng)(zheng)(zheng)長(chang)(chang)(chang)(chang)(chang)(chang)巖(yan)(yan)、方鈉(na)(na)(na)正(zheng)(zheng)(zheng)長(chang)(chang)(chang)(chang)(chang)(chang)巖(yan)(yan)、鈣(gai)霞(xia)(xia)(xia)正(zheng)(zheng)(zheng)長(chang)(chang)(chang)(chang)(chang)(chang)巖(yan)(yan)、假(jia)白榴正(zheng)(zheng)(zheng)長(chang)(chang)(chang)(chang)(chang)(chang)巖(yan)(yan)和(he)(he)方沸正(zheng)(zheng)(zheng)長(chang)(chang)(chang)(chang)(chang)(chang)巖(yan)(yan)。 　霞(xia)(xia)(xia)石(shi)(shi)正(zheng)(zheng)(zheng)長(chang)(chang)(chang)(chang)(chang)(chang)巖(yan)(yan)常(chang)構(gou)(gou)(gou)成(cheng)單一或復雜(za)的(de)巖(yan)(yan)株，有(you)時在片麻巖(yan)(yan)中(zhong)呈整合侵入(ru)體，具似片麻狀(zhuang)構(gou)(gou)(gou)造。有(you)時構(gou)(gou)(gou)成(cheng)巖(yan)(yan)盤、巖(yan)(yan)盆或巖(yan)(yan)墻(qiang)。

　　霞石正長(chang)巖常與(yu)堿(jian)(jian)性正長(chang)巖、堿(jian)(jian)性花(hua)崗巖有(you)成因聯系;有(you)時通(tong)過(guo)堿(jian)(jian)性二長(chang)巖與(yu)堿(jian)(jian)性輝長(chang)巖密切相關。于此種(zhong)情(qing)況，偶爾出現(xian)黃長(chang)巖。