PR69 is a grading designation.
PR = Proof. Proof silver eagles are made by the US mint for sale directly to collectors.
69 is a numerical grade assigned to the coin by a grading company then slabbed. The scale used is from 1 to 70.
most proofs silver eagles will grade 69 with a small number 70.
DCAM = deep cameo.
I will assume the ones you have are uncirculated, these are the ones sold by the US Mint to designated distributors who in turn sell them to dealers who sell them to collectors. sold to collectors about $1.50 over spot price of silver.
The proofs come from the mint packaged with certificate, and removed to get the grade PR69 DCAM or any other grade not loose like the uncirculated ones.