sqlite3 shortens float value

I do a simple:

latitude:String = String.fromCString(UnsafePointer(sqlite3_column_text(statement, 11)))!

The value in the Database is "real". In the database I have 51.234183426424316 (verified using Firefox'SQLite Manager)

With the above I get in my String only: 51.2341834264243 (the last two digits are missing with is not acceptable working with coordinates)

Any explanations? Solutions?