I am reading Germinal by Zola and I am astounded by it… I had never heard of the book or the author

I am not far into the book but the writing about the coal mine is so good I feel anxious and claustrophobic. The cold weather is described in a way that makes you really feel it's biting grip. it's everywhere and you can't escape it. When it describes the horses working in the mines it made me feel profoundly weary of mankind. It's one of the best books I've started in a long time and I am wondering if I am just ignorant for not knowing about it or if Zola is an under appreciated author?