Like Min said, Ur of the Chaldees was at earliest founded at 1,000BC. It is not the same Ur as the ancient city of Sumer. Also, even if Abraham/Ibrahim was from Ur where writing was invented, it's very improbable that he would've been able to write. Writing was mainly used for records and by the wealthy denizens of Sumer, not by random goat herders. This was still the case around 200 years ago, let alone over 4,000.
If more of us valued food and cheer and song above hoarded gold, it would be a merrier world. - J.R.R Tolkien
