How to tell the authenticity of a silver dollar? Tell me in detail.

Real silver dollar is characterized by clear and loud sound and rhyme, which produces reverberation when colliding with each other, otherwise it is false; Look at the white face of the coin, the pattern is natural and clear, and the color is delicate and rich. Of course, the process of real careful identification can be summarized into four aspects: listening, looking at shape, weighing and fixing color. Listen to the sound. This is the main method of silver dollar identification. Where the color of silver dollar is high, the sound is generally soft and pleasant. The silver dollar with insufficient color has a hoarse, short and turbid voice because of its high copper content. False silver vowels are long, sharp, high or low. The first way to listen is to "knock", gently hold the center of the silver dollar with the tip of the thumb and the tip of the middle finger of the left hand, and tap the edge of another silver dollar with the right hand to hear its voice. Pick out the extremely suspicious silver dollar before identifying it. Second, by touching, take a certain number of silver dollars (about 8 to 25 pieces) with your right hand, slide it down to your left hand for 45 degrees, listen to the sound of collision, and identify it with patterns and patterns. Look at the shape The stamping pressure of real coins is moderate, and silver coins are cold-pressed into various words, patterns and patterns. Their colors are bright and natural, their patterns are moderate in depth, their edge lines are even in thickness and their spacing is consistent. People, hair, beards, spikes and other nuances are clear and tidy. Weigh. Generally, the circulation time of real silver dollars is different, and the degree of wear is different. But the quality of the same variety and version of silver coins will not be different1g. For example, the average weight of a round silver coin is about 26.5 grams, and the average weight of a semicircle is about 13.25 grams. If the fineness reaches 88%, it is a real coin. Set the color. Identify the fineness of silver dollar that does not meet the standard of silver dollar. Nitric acid solution can be used for field test. First, clean a certain part or file a small mouth. After dripping nitric acid, if green foam appears, it means that its color is not high. Judging from its color, the color of silver dollar with purity above 92% is basically unchanged. If the fineness is 90%, its color is yellow or light brown. The fineness is about 80% and the color is dark brown. The color is about 70%, light green. If the fineness is about 50%, it is dark green. The mass counterfeit silver coins found in the market are mainly made of copper, nickel and other alloys, with different characteristics: some are modeled after the pattern of "Yuan Datou" silver coins in the third year of the Republic of China, the color is white and gray with cyan, dull and short-sounding, similar to other private editions; Some are smaller than the normal silver dollar 1 mm, and the important thing is that the mass is always about 20 grams. There are also a few fake silver coins made of copper, lead, tin and other metals, and the surface is silvered. They are characterized by rough layout, short sound point and light weight, and the worn silver is mostly pale yellow, with a mass of about 2 1 g; The fake silver dollar made of tin and aluminum has a vague pattern, soft and inelastic texture and a low voice. Grinding away silver, tin is bluish gray; Aluminum is bluish black with a mass of about 20g. In addition, due to the long-term continuous exchange and circulation of silver coins, through the touch and friction of human hands, the worn part is mainly manifested in the prominent part of the money body, which should be natural, smooth and even, without directionality. Therefore, generally, high-grade silver coins with packaging, no wear and no patina can be judged as counterfeit money.