Ella collects dimes, quarters, half dollars, and $1 coins in her piggy bank. When she opens it, the number of dimes equals the number of half dollar coins. The number of quarters also equals the number of $1 coins. Knowing that there is at least one of each coin in the piggy bank and that the value of the coin collection is between $10 and $12, find the number of unique possible combinations of coins in the collection.