I am trying to date a family heirloom concertina, LACHENAL, serial number 42759, an Anglo student model I believe. I have no knowledge of why it had resided in our cupboard since I was born (1935) in Adelaide, South Australia. I have some information from the Wheatstone Ledgers with our family name mentioned in a purchase in 1853. If this serial number goes back that far, it will be a great story. The rosewood fretwork, ivory buttons, intact faded soft velvet lining, and a restored bellows make it a lovely little instrument. I would also like to know its worth. Thanking you if I can trace its history.