在广东大顶锡铁矿的镁矽卡岩体中,存在一种罕见的含硼矿物—碳硼硅钙镁石(harkerite)。这一矿物,是蒂利(Tilley)1948年在苏格兰斯凯岛的镁矽卡岩中首次发现的。60年代以来,又相继在西伯利亚雅库特和阿拉斯加苏厄德半岛的同类型矿床中见到。大顶锡铁矿位在石背岩体与三叠系上统白云岩层的接触带。那里的镁矽卡岩相当发育。镁矽卡岩的主要矿物为镁橄榄石、镁尖晶石及深绿辉石。镁矽卡岩的 In the magnesium skarn body of the Dading Tin Mine in Guangdong Province, there is a rare boron-bearing mineral, harkerite. This mineral was first discovered by Tilley in Magnesium Skarn on the Isle of Skye, Scotland, in 1948. Since the 1960s, it has been seen in the same type of deposits in Yakutia, Siberia and Seychelles, Alaska. The Dading tin deposit is located in the contact zone between the dorsalite body and the Triassic upper dolomite layer. Magnesium skarn there quite developed. The main minerals of magnesium skarn are forsterite, magnesium spinel and pyroxene. Magnesium skarn