The current value of a 1980 P-D-S Mint set is $8.00.
If you have the entire collection of coins that were minted that year and these coins are all in uncirculated condition, the value ranges from $8 to $12.
These coins are no longer in circulation since Irelands changeover to the Euro in 2002. Unless they are part of a Proof or Uncirculated mint set or are individual Proof or Uncirculated coins and in absolute mint condition, they have little or no value.
These coins are still potentially in circulation so, unless they are part of a Proof or uncirculated mint set or are individual Proof or uncirculated coins and in absolute mint condition, they are worth Two Pence.
It's not silver and regardless of mintmark the value is $1. Only a proof or uncirculated coins sold from the Mint will have more than face value.
Brass not gold. Just the Mint issue uncirculated coins have very small premiums above face value.
The US Mint did not issue any silver coins of any kind in 1980. If you have silver coins dated 1980, they are not US coins.
The S.B.A. coins have very little collector demand. Uncirculated coins of all dates & mintmarks are very easy to find. It would have to be in the MS-65 or higher grade to be worth more than face value.
If you have obtained an annual uncirculated 1975 yearly set, its present value is: $15.00.
About ~20 cents over face value as a set. They contain no silver and uncirculated sets (Even more so than proof sets!) have very little collector demand at the moment. So you should add up the face value of all the coins in the set then add 20 cents to that and that is about the value of the set (assuming it is in mint packaging).
NO, they do not. That's the simple answer.
The 1970 Uncirculated US Mint Set is valued at $18.
There is no such thing as a Presidential quarter. These are dollar coins. They are not gold. They are brass. They are worth around $2.00 in uncirculated condition. These coins are very common.