金铜佛像有青铜、黄铜、红铜和其它铜合金等，但不同时期的用铜是不一样的，元代以前的铜佛一般都用青铜，也有一些红铜制品，元代以后则出现了较多铜锌合金的黄铜及纯铜制作的所谓红铜佛像，而在青铜上鎏金的佛像一般被称为金铜佛像，黄铜佛像大多是不鎏金的;佛像的面部五官、身材比例、肌肉和衣纹特征等，不同的朝代，即使是同一朝代的不同时期也是有许多变化的，比如隋唐两个相连的朝代，虽说佛像的整体风格是相近的，但面相还是略有区别的，隋代的佛和菩萨为半圆脸型，唐初起就变得稍瘦一些;古代的金铜佛像或其它木质、陶瓷等材质的佛像，在长时期受人们供奉时被烟火熏染过，或是长时期埋藏于地下。只要对其仔细进行嗅别，一般都可以嗅到烟火、发霉或发朽的味道，而现代仿制品则完全没有这种味道，即便是有些伪品用烟熏或埋于地下等作旧方式处理，也难免露出破绽，或烟火味过浓，或泥土味太重，容易被行家识破。
Bronze Buddha statues include bronze, brass, red copper and other copper alloys, but the copper used in different periods is different. Before the Yuan Dynasty, bronze Buddha was generally made of bronze and some red copper products. After the Yuan Dynasty, there were more so-called red copper Buddha statues made of copper zinc alloy brass and pure copper. The Buddha statues gilded with gold on bronze are generally called gold copper Buddha statues, and most of the brass Buddha statues are not There are many changes in the facial features, body proportions, muscles and clothing patterns of Buddha statues in different dynasties, even in different periods of the same Dynasty. For example, in the Sui and Tang Dynasties, although the overall styles of the Buddha statues are similar, their faces are slightly different. The Buddhas and Bodhisattvas in the Sui Dynasty have a semicircular face, which has become slightly thinner since the early Tang Dynasty; Ancient gold bronze Buddha statues or other wood, ceramic and other material Buddha statues were smoked by fireworks when they were worshipped for a long time, or buried underground for a long time. As long as they are carefully sniffed, they can usually smell pyrotechnics, mouldy or rotten flavor, and modern imitation is completely without this smell. Even if some counterfeit products are treated by smoke or buried in the old way, it is inevitable to expose flaws, or the smell of pyrotechnics is too strong, or the soil is too heavy to be seen by experts.