This is a highly collectable piece of Mid-Century Modern British tableware designed in the late 1960s or early 1970s.  Produced under Meakin's "Studio" line, well known for its trendy, geometric and nature inspired pop art designs during the era.
 
The "impact" pattern features a striking psychedelic floral medallion motif in shades of blue, teal and green, set against a crisp white ironstone background.