Rocks And Mineral

To day I read a book about Rocks and Minerals
Reading Response

I didn't know that the Earth has has been around for 4,600 million years.

I found out that platinum is more valuable then gold.

I didn't know that Obsidian is formed by lava rapidly cooling.

I found out that rocks can be formed by gases.And this is how it happens when dormant or dying volcinic gases may escape and hot springs form and this is how this is how some rock get formed.