普通晚唐开元在唐宪宗元和年间之后铸造，一直持续至唐亡。它沿袭了中唐开元的特点。从质地上看，这种开元通宝所用铜料很杂，说不清是何种铜合金，铜质发黑，纯度低，含铁量高，个别可被磁铁吸引。从形体上看，质量较小，普遍不超过4克。钱径在23毫米至24毫米之间。铸工草率，多数轮廓不整，普遍不如中唐开元精美。很多应属私铸之列。从钱文上看，正面钱文笔划比较纤细，与中唐后期的钱文一致，但字迹模糊。在背文上，多有小型月痕，对月月痕，多月痕及孕星开元出现，还有合背开元。它们普遍做工粗糙，有的连钱文都难以辨识。
The ordinary late Tang Kaiyuan was cast in Tang Xianzong after the Yuan Dynasty and the reign of the Emperor, and it lasted until the death of the Tang Dynasty. It follows the characteristics of Kaiyuan in the Middle Tang Dynasty. In terms of texture, this kind of copper material used in Kaiyuan Tongbao is very miscellaneous. It is not clear what kind of copper alloy it is. The copper is blackened, low in purity and high in iron content, and can be attracted by magnets individually. From the physical point of view, the quality is relatively small and generally does not exceed 4g. Money diameter is between 23 mm and 24 mm .. Founders are sloppy and most of them are not well - contoured, which is generally not as elegant as the Kaiyuan of the Middle Tang Dynasty. Many should belong to private casting. From Qian Wen's point of view, Qian Wen's strokes on the front are slim, consistent with Qian Wen's in the middle and late Tang dynasties, but the handwriting is fuzzy. On the palindrome, there are many small moon marks, opposite moon marks, multiple moon marks and pregnant star marks, as well as the combined palindromic marks. They are generally rough in workmanship, some of which are difficult to identify even Qian Wen.
听声音
开元通宝，尤其是初唐的，用料讲究，做工较为细腻，因年代久远，内部成分会有变化。铜质被氧化，尽脱火气。将真品开元掷于地上，清脆响亮，有一定弹性，声音低沉则证明其内部有裂。
闻气味
真品开元通宝很多都是罐装窖藏有纯正的泥土香味，而伪品锈色来源于迅速的化学反应，往往有刺激性气味。
探针法
用缝衣针对生坑开元通宝进行试挑，把缝衣针针头向下竖直下压，放手后，真品开元通宝上的缝衣针会掉下去，而伪品由于做的锈往往富有一定弹性，针不会掉落。
Listen to the sound Kaiyuan Tongbao, especially in the early Tang Dynasty, is exquisite in materials and workmanship, and its internal composition will change due to its long history. The copper was oxidized to remove all internal heat. Throw the real coin on the ground, it is crisp, loud, elastic and has a low voice, which proves that there is a crack inside. Smell Many of the authentic Kaiyuan Tongbao are canned hoards with pure soil flavor, while the rust color of the fake comes from rapid chemical reactions and often has pungent odor. probe method Try to pick out the sewing needle for Kaiyuan Tongbao in Shengkeng with the sewing needle pressed down vertically. After letting go, the sewing needle on the genuine Kaiyuan Tongbao will fall, while the fake product will often be elastic due to the rust it makes and the needle will not fall
比较密度
密度是物质的一种特性，可以拿与几个开元通宝相同质量或相同体积的同种物质，真品的开元通宝在相同质量的情况下，体积也相同。而伪品在相同质量的情况下，体积比它同一种物质大；在相同体积的情况下，质量比它同一种物质小。如果是不同质量和不同体积的，而且是同一种物质的，则计算它们的密度，再比较，密度与同一种物质相同或接近的是真品，但是密度比同一种物质小的是伪品。
Comparative density Density is a property of matter. It can take the same mass or volume as several Kaiyuan Tongbao. The original Kaiyuan Tongbao has the same volume under the same mass. However, under the condition of the same mass, the volume of the fake product is larger than that of the same substance. Under the condition of the same volume, the mass is smaller than that of the same substance. If they are of different mass and volume and are of the same substance, then their density is calculated and compared. If the density is the same or close to that of the same substance, it is genuine, but if the density is smaller than that of the same substance, it is fake.
鉴别技巧
对于会昌开元鉴别应加以注意。史料记载会昌开元有23种，是各州钱局铸钱时于钱背加盖铸局地名的一类特殊开元钱，这种开元通宝钱币字体十分随意，很不规整。其中特别注意扬州局所铸钱币为纪念会昌灭佛，背面为“昌”而非“扬”。若发现文字秀丽规范，或背文有“扬”者，定为伪古。另外，保存钱币入盒袋即可，钱文应朝下或内置，以防磨损。
Identification technique Attention should be paid to the identification of Huichang Kaiyuan. According to historical records, there are 23 kinds of Kaiyuan in Huichang, which is a special kind of Kaiyuan money stamped with the place names of each state's money bureaus when they cast money. This type of Kaiyuan Tongbao coin is very random and irregular. Among them, special attention was paid to the coin cast by Yangzhou Bureau to commemorate Huichang's destruction of Buddha, with " Chang" instead of " Yang" on the back. If it is found that the writing is beautiful and standard, or if it has " Yang" on its back, it will be regarded as a pseudo - ancient. In addition, just keep the coins in a box bag. The Qian Wen should be downward or built in to prevent abrasion.
