No ballot shall be counted which is marked contrary to law, except that no ballot shall be rejected for any technical error unless it is impossible to determine the voter's choice. If two or more ballots are found folded together among the ballots removed from a ballot box, they shall be deemed to be fraudulent. Such ballots shall not be counted. They shall be marked "Fraudulent" and shall be placed in an envelope indorsed "Not Counted" with the reasons therefor, and such envelope shall be delivered to the board of elections together with other uncounted ballots.
No ballot shall be rejected because of being marked with ink or by any writing instrument other than one of the pencils provided by the board of elections.