I love enamel and this mid century modern brooch by J. Tostrup fits the bill! It is in a vibrant blue colour. It is marked 'Sterling J Tostrup Norway'. As it does not have a British (or equivalent) Hall mark it cannot be sold as Sterling in this country. However Tostrup is a very respected Norwegian firm so I am quite happy about it. Full details are on my web site - including dimensions. Ref: 2606 B130/7 Price £115 - and there are more photos.