By the anvil make and your last word signing off, I'll assume you're in Australia?
Not JUNK at all, quite valuable, especially in Australia... I think the guys working for you were licking their chops at getting a valuable item snuck out of your garden.
Value will depend on condition and size. Can't quite tell the size from the picture. Some BK anvils will have the number cast into the side. If not, take overall measurements of total length, height, and top face width.