The use of private seals upon all deeds, mortgages, leases, bonds, and other instruments, and contracts in writing, including deeds from a husband to his wife and from a wife to her husband for their respective community right, title, interest or estate in all or any portion of their community real property, is hereby abolished, and the addition of a private seal to any such instrument or contract in writing hereafter made, shall not affect its validity or legality in any respect.