Scottish Silver Brooch, Mid to Late Victorian, Antique, Agates

Antique Scottish sterling silver and agate, plaid or kilt brooch, octagon in shape with 8 lobes of polished agate skillfully cut to lie flush and form a circular shape. There is pink, brown mottled, dark and light, moss agate, and white agate, all fitted against and within sterling silver back plate. 4cm across which is around an inch and threequarters. Period; 1850s to 1870s, no marks neither hallmark or makers mark which is not unusual for Scottish silver jewellery of this age.