闪长玢岩（Diorite-porphyrite）
产地：山东省新泰市
特征：
闪长玢岩（Diorite-porphyrite）是闪长岩类的浅成岩或超浅成岩，具明显斑状结构，其斑晶多为斜长石和普通角闪石，偶见黑云母。岩石整体颜色多为灰及灰绿色。以碱性长石或石英为斑晶的喷出岩和浅成岩，基质为细粒或隐晶—玻璃质。副矿物有磷灰石、磁铁矿、榍石、锆石等。中国安徽马鞍山和南京附近的辉石闪长玢岩，与铁矿关系密切，形成“玢岩铁矿”。
岩石呈深灰色，基质具细粒不等粒粒状结构。主要由斜长石（60%±）、钾长石（13%±）、石英（10%±）、角闪石（8%±）等组成，斑晶为斜长石和角闪石，有少量的石英。斜长石斑晶粒径0.3-3mm，多为板状，具密集的环带构造，常被绢云母、高岭石交代，角闪石斑晶呈大小不等的长桩状，常被方解石交代。基质主要为石英和钾长石，次为斜长石和暗色矿物，粒度一般在0.1毫米左右。闪长玢岩常呈岩床、岩墙产状，或为闪长岩的边缘相。
采集人：马玉新
Diorite-porphyrite
Provenance: Jiangxi, China
Characteristics:
Diorite is an intrusive igneous rock composed principally of the silicate minerals plagioclase feldspar, biotite, hornblende, and/or pyroxene. The chemical composition of diorite is intermediate, between that of mafic gabbro and felsic granite. Diorite is usually grey to dark-grey in colour, but it can also be black or bluish-grey, and frequently has a greenish cast. It is distinguished from gabbro on the basis of the composition of the plagioclase species; the plagioclase in diorite is richer in sodium and poorer in calcium. Diorite may contain small amounts of quartz, microcline, and olivine. Minor amounts of muscovite may also be present. Varieties deficient in hornblende and other dark minerals are called leucodiorite. When olivine and more iron-rich augite are present, the rock grades into ferrodiorite, which is transitional to gabbro. A dioritic rock containing feldspathoid mineral/s and no quartz is termed foid-bearing diorite or foid diorite according to content.
Gatherer: Ma Yuxin