The example pictured above, a horse brooch
dating to the 1st to 3rd Centuries AD, while not unknown, is a very
uncommon type. It has been modeled in the round rather than as a flat
plate with pin on the reverse. For more details, it may be viewed here: http://www.clioancientart.com/catalog/i475.html
For many more examples of brooches, mainly Roman, of many different types, visit the “Ancient Jewelry and Personal Adornment” section of our website at: http://www.clioancientart.com/catalog/c19_p1.html
All the brooches presented above are individual UK metal detector finds, declared not treasure and legally exported.
For further study, we recommend the following sources:
Roman Brooches in Britain, a Technological and Typological Study Based on the Richborough Collection, The Society of Antiquaries of London, 2004
AND
A Visual Catalogue of Richard Hattat’s Ancient Brooches, Oxbow Books, Oxford, 2007