There was no C series 1966 $100 US Notes, only plain and A.
Please see the Related Questions for more information.
Please check your bill again and post a new, separate question. The last red-seal $100 bills were dated 1966. All 1969 $100 bills were issued as green-seal Federal Reserve Notes.
The red seal as well as the banner across the top of Franklin's portrait indicate your bill a United States Note and not a silver certificate. Please see the question "What is the value of a 1966 US 100 dollar bill?" for more information.
All 1966 US $100 bills have red seals. If yours is gold it could be faded or was exposed to a chemical such as bleach. Either condition would reduce its value to a collector. Please see the Related Question for values of undamaged 1966 $100 bills.
Please check the date on your bill again and post a new, separate question. The last red-seal $100 US Notes were dated 1966. Any 1985 US $100 bill should have a green seal and the words "Federal Reserve Note" across the top.
Please don't assume that every old bill is a silver certificate. The last $100 silver certificates were printed back in 1891. The red seal and banner reading "UNITED STATES NOTE" at the top of your bill indicate it's a US Note rather than a silver certificate. Please see the question "What is the value of a 1966 US 100 dollar bill?" for more information.
It's a 1966 A $100 Red Seal Elston/Kennedy bill, nothing more.
Please check your bill again and post a new, separate question. The last red-seal $100 bills were dated 1966. All 1969 $100 bills were issued as green-seal Federal Reserve Notes.
The red seal as well as the banner across the top of Franklin's portrait indicate your bill a United States Note and not a silver certificate. Please see the question "What is the value of a 1966 US 100 dollar bill?" for more information.
All 1966 US $100 bills have red seals. If yours is gold it could be faded or was exposed to a chemical such as bleach. Either condition would reduce its value to a collector. Please see the Related Question for values of undamaged 1966 $100 bills.
Please check the date on your bill again and post a new, separate question. The last red-seal $100 US Notes were dated 1966. Any 1985 US $100 bill should have a green seal and the words "Federal Reserve Note" across the top.
Please don't assume that every old bill is a silver certificate. The last $100 silver certificates were printed back in 1891. The red seal and banner reading "UNITED STATES NOTE" at the top of your bill indicate it's a US Note rather than a silver certificate. Please see the question "What is the value of a 1966 US 100 dollar bill?" for more information.
$100
The U.S. didn't print any $2 bills dated 1968, and the last red-seal U.S. Notes were $100 bills dated 1966. Please check again and post a new question.
Please don't assume that every old bill is a silver certificate. The banner across its top and the red seal indicate it's a United States Note, a form of paper money issued directly by the Federal government. US Notes were discontinued in the 1960s. There's more information at the question "What is the value of a 1966 A US 100 dollar bill?".
At least $40. In almost-new condition its value can be over $100.
Please check your bill again and post a new, separate question.> The last red-seal notes were $100 bills dated 1966.> All $2 bills printed since 1976 have green seals.> No US bills were printed with a 1983 date.If your bill's date is actually 1963, there's more information the at question "What is the value of a 1963 US 2 dollar bill?".
depending on condition, it can be worth 5$ up to about 100$