The value would depend on the year and condition, but most Irish coins aren't worth much unless they're part of a mint set.
1p
Prior to 1971, 1p was known as 1d. They would have very little value. They are no longer legal tender, but a lot of Irish homes would have them and people who visited Ireland up to 1971 may also have them.
See the link below. It shows a 1980 1p, but other than the year any Irish 1p from 1971 to 2001 would look the same.
Such a coin does not exist. The Irish 10 Pence coin was first issued in 1969.
To make 10 pence using coins, there are several possible combinations. You could use one 10p coin, two 5p coins, a 5p coin and five 1p coins, or ten 1p coins. These are the four distinct ways to make 10 pence with coins.
All Irish coins have the word "Éire" on them. The value depends on the condition and the denomination.
Very little, probably £1 to £2 max.
The mass of an English penny coin is 3.56 grams.
A British 2003 Uncirculated coin set (10 coins - £2 to 1p) could fetch up to £14 GBP. A British 2003 Proof coin set (11 coins - £5 to 1p) could fetch up to £34 GBP. It should be noted that the value of any "coin set" is dependant on it being in its original packaging and condition. A reputable coin dealer will be able to give a more accurate valuation.
1p
From decimalization until 1991, the 1p coin was bronze. From 1992 onwards, it has been copper plated steel.
Well, isn't that a happy little riddle! If one of the coins is not a 10p coin, then it must be a 1p coin. So, you have a 10p coin and a 1p coin in your hand, making a total of 11p. Just like painting, sometimes it's the small details that make the big picture come together beautifully.