All futures products are graded, and the prices of different grades may vary greatly. Take the corn you mentioned as an example. The delivery variety is GB 1353- 1999 yellow corn. When you want to know the spot price, you should start with this variety of corn. However, the spot price of agricultural products is generally confusing, because not only the variety but also the place of origin will affect the price of agricultural products. Generally speaking, the price of the State Reserve Bureau is worthy of reference, and then the CIF price.

I suggest you study more non-ferrous metals first. Relatively speaking, the spot price of metals is much simpler and will not be as chaotic as agricultural products.