化學組成, 鍵及結構：(礦物)

新生代上新世

Chemical composition, bonding and structure: (Mineral)

The Pliocene in Cenozoic

原生物：(化石)

角礫岩的形成是由破碎了的尖角岩石、或礦物碎片經過堆積，受到壓缩力而壓緊，再因水中的黏性礦物，如矽石和方解石，而黏合在一起形成石頭。整個過程又稱岩化作用。

Living Specimens: (Fossil)

Breccia forms where broken fragments of rock or mineral debris accumulate, compacted by compressional force through the process of compaction, and bounded together by mineral cement like silica and calcite through the process of cementation. The whole process was known as lithification.

角礫岩的粒徑是粗粒。它包含了巨礫 (直徑不少於256毫米)，中礫(直徑介乎64毫米至256毫米)和小圓石(直徑介乎2毫米至64毫米) 。大多數角礫岩是由不同種類碎石和礦物碎片混合而成的。

The grain size of Breccia is coarse-grained. It contains particles of boulder (diameter >256mm), cobble (diameter from 64mm to 256mm) and pebble (diameter from 2mm to 64mm). Most Breccia are a mix of rock fragments and mineral grains.

因其引人注意的外表，它被用在雕塑和建築物料，如柱和牆上的表面物料。如果角礫岩夠堅硬，它能夠用作建造道路上。以往古埃及人亦有使用。

The striking visual appearance of breccias has for millennia made them a popular sculptural and architectural material. It is most often used as an ornamental or facing material in walls and columns. If hard it can be used as aggregate, fill etc. in the construction and roading industries. Breccia was used on a limited scale by the ancient Egyptians, for example the statue of the goddess Tawaret in the British Museum.

本港的角礫岩主要分佈在新界東北部的離島，如吉澳北部及鴨洲。

It is found mainly Islands in the northeast New Territories, such as the northern Crooked Island and Robinson Island (Ap Chau).

角礫岩沒有特定的顏色。這是由於母石和礦物不同，混合起來的顏色會有異。

Breccia can be any color. It depends on the color of the matrix or minerals.