Grading Coins is the single most important skill for a coin collector to have.
This book will help you piece together each component: surfaces, luster, strike,.
There is plenty of Science involved - but there is also an art to the skill of grading.
Very few books go through each facet of Grading and explain them in depth, in easy to understand terms that even a novice can understand.
Plenty of books will show you pictures of Coins in various grades, and ask you to match the coin to a picture.
Grading Coins is the single most important skill for a coin collector to have