FM Konstglas Ronneby Sweden Full Lead Crystal Bubbly Fumato Art Glass Bird Artist Signed FM Ronneby Sweden R3 Rare Vintage 1970's Find. Excellent Condition, no chips, cracks or scratches, has been well cared for. Same or next day USPS Shipping. A stunning Scandinavian full lead crystal grey + clear glass fish sculpture. Made by FM Konstglas (which later became Marcolin Art Crystal) of Ronneby, Sweden. Signed to base "FM, Ronneby, Sweden, R 3". The feathered bubble effect is usually referred to as "sfumato", which in glass terms means a gradual change of shade, however it has recently been discovered that the correct term would be "fumato", which means "smoked", a technique which involves exposing the glass to smoke from a fire, to give the glass a smoky colour by picking up particles of unburnt ember and ash from the smoke. Measures approx 6.75 inches tall by 4 inches in diameter at widest point.