Fine Grinding Material

The reason that grinding material is done is so that the particles of gold and other valuable elements can be liberated from the material that they are enclosed in. the ideal is for the material to be ground down fine enough in order to be able to find the gold and valuable minerals. In most cases, it will only be possible to pulverize them down to a certain amount of fineness though. In the case of coarse particles for example, it is usually possible to grind them down pretty easily until they are able to go through a 60 mesh screen, however it will become a lot more difficult to grind every time the size of the coarse particles becomes reduced. It is suggested to start out by using a smaller screen when the grinding is being done for panning because this will help to assure a certain amount of fineness that would not be able to be accomplished otherwise. The smaller the bits of particles are the easier they are to pan. A good quality screen can even be made by hand; all that is needed is a piece of 60 or 80 mesh screen and to solder it onto a little tin can that has had the ends removed and that is smooth.

Tail up
After you have gathered the concentrate, it will be necessary to check it very well. One of the ways in which it can be tested is by placing some in a pan with water and to then tilt the pan or rock it gently in order for the water to run out of the concentrate in an direction between the side and the bottom of the container, which will take the particles that are lighter in weight to the end of the concentrate. This will need to continue being done until all of the smaller pieces have moved along and to where it leaves the heavier material, such as gold in this case, in what is known as a tail or colors, which is the main concentrate. The good thing in the case of gold, if there is a good amount of gold in the tail, it will not be difficult to recognize. Even if you are able or not able to see a tail, it will still be necessary to check the concentrate very carefully, preferably with a hand lens. If you are only able to see a teensy bit of gold particles in it, then it is possible you cannot see the rest without the help of a hand lens. One tip to remember is that usually the little gold particles have a tendency of rolling along the water, which is a characteristic that can help you find them. 

Roasting
When panning is done it is common to find a pretty large amount of sulphides in it. Given that these particles can sometimes be the same in weight as the fine pieces of gold, it will make it harder to tail the gold out. It will be difficult to know exactly how much gold can be found or if there is any gold at all. However there is a trick that can help. There is a process that is known as roasting and in this process the sulphides get eliminated by literally burning them. It is very recommended to roast whenever a good concentrate of sulphides has been obtained and mainly because the fine little particles of gold are often times trapped in side of the bigger pieces of sulphide and it is necessary for these to break up in order to find the gold inside. One of the best ways of doing this is by drying the concentrate that has been retrieved by panning it. This concentrate will then need to be put on a tin top. The lid should be very carefully placed over a hot fire. You will soon start to see it burn and this should keep on being done until you are no longer able to see any sulphur nor should you see any arsenic fumes coming out of it. After this has been done, you will need to take if off of the fire and allow it to cool down. The rusty remains will need to be placed in a mortar and should be ground down fine to where it turns into a powder. This should then be moved over to the gold pan, should get washed gently, and then checked as would be done with the tailings. If there still remains to be a good amount of sulphides in it, a second roasting should be done to remove it. If you are working in an area that has a great amount of sulphides, you can become prepared for the process by including some cheap potassium chlorate. This will need to be mixed with the sulphides before it is heated. After the warmth has been put over it, you will see how the chlorate decomposes, which will provide oxygen that will considerably speed up the burning process of the sulphides and will assure the roasting has been done more thoroughly.