Sand sinks and coffee grounds float.
I'd start there.
I'm not sure what form the coffee is in, however unroasted raw beans might not float, and if it is instant coffee then you would probably ruin the product.
As salt is soluble in water, mixing salt and sand in water would result in solid sand, and salt water. When poured through a coffee filter, the sand would remain in the filter, while the salt water would flow through. After letting the water evaporate, salt would remain. You will be left with the two separated solids.
get a strainer to get the sand out silly :)
With a sieve.
we can separate sand by decanting
You can separate them by filtration and it would help because when you add water the sand would stay because you would have to add cold water so that the sand will stay and the salt will go through.
Weigh each sample and then make a solution of coffee, sand and water. First of all, we have to filter the solution with the help of filter paper so all the water will pass through the paper and as a filtrate we will have coffee and sand. Take the filtrate and let it dry. Secondly, once the filtrate is dry take a strong magnet and scan across, underneath the filter paper. This will separate all the sand on one side of the filter paper. Finally, record the mass of each component after the experiment.
it would be like thou sand
Iron can be separated from sand using a (electro)magnet.
we can separate them by sublimation as iodine sublimes on heating.
Sublimation
I would sort them by a strainer
Add water, It separate woodchip(float) and sand(down)