Here is coin #1 the coloring is darker on both sides than in the photo. coin #2 coin #3 is the most worn of these dollars. coin #4
All of the coins pictured are in various stages of circulated condition. Coins 1 & 3 would receive no grades because they are damaged. Coins 2 & 4 would be around VF and XF respectively. This link should help you some with learning about grading - http://www.coingrading.com/intro1.html But I would also suggest that you look for and purchase the ANA Grading Guide and the PCGS Grading Guide.
I have the one and two other photo grading guides but there is some things that are a little fuzzy and experienced hand helps. Thanks.
Photo grading guides are of little use, in fact they are far more harmful than good in my opinion. That is because they show you a picture of 1 single coin, and that will if anything lead you to under-grade or over-grade coins. And that is because if you looked at 100 pictures of a single coin, 100 different examples, all the same date/mint, and all graded by the same TPG at the same grade, almost all of them would look different from each other. Yet they are all the same grade. So how can you possibly learn how to grade a coin from looking at pictures of 1 coin in a given grade ? Answer, you can't. You are far better off learning the written descriptions and grading standards for each grade, and then looking at thousands of coins, in hand, that have already been graded, if you want to learn how to grade. Doing that will teach you how and why so many different coins that all look different than each other, can all be graded exactly the same. Or, be graded differently. Never rely on pictures of a single graded coin for comparison purposes so you can grade another coin.
One thing you need to understand is that you cannot really learn how to grade a coin simply by comparing coins to photos in a grading guide. Your coins will not look exactly like any coin in a photo is a grading guide. Every coin is different. You need to first learn HOW to grade a coin and then gain experience grading coins once you know what to look for. You need to concentrate on understanding: How the coin was made (struck) What a full strike, less-than-full strike, weak strike, etc. look like and how they occur What luster is, how it occurs and how to identify it The difference between wear and a coin that is not fully struck up (luster usually comes into play here) The places on the coin where wear usually occurs first (typically the highest points on the coin) Once you have a basic understanding of these things then you should be able to learn how to grade coins.