Answer:
I am pronounced as one letter written with three. I come in blue black brown or grey. Reverse me and I read the same either way.
My first is in some but not in all. My second is in tiny but not in tall. My third in little but no in big. My fourth in port but not in pig. My whole is made in nature's way. For clothing rugs used every day.
I am in the past never in the future. I don't exist but have existed. I saw what you saw and that is what I will ever see.
I am the key that is the hardest to turn
When I come in from sea to shore twenty paces you'll see No less no more.
I am rarely touched but often held. If you are smart you'll use me well. What am I?