I am not sure if this made of sterling silver or some NS / alloy as no regular hallmarks noticed. Manufacture of Ludv. Sæthers Gull- og Sølvvareverksted in Oslo. Stylish lovely leaf shape ashtray (Art Nouveau, Jugenstil). Hand casting and enamel coating of quality. 

Size app.: 8,6 cm long (~ 3,4 in) by 6,9 cm (~ 2,72 in) deep. Very good; age n usage wear. Please study high-res pictures for cosmetic condition! In person actual item may appear darker or brighter than in our pictures, strictly depending on sufficient light in your environment. Weight of app. 0.045 kg it is going to measure some 0.25 kg of volume packed for shipment.