On 4 July, 17:01, Stuart Noble wrote:

I'd try a clear sealer. Won't be as good as a glaze but it should
restore the colour.

Our Victorian gateposts have huge great terracotta pyramids on top of
them,

I've just had great success taking off several layers of peeling paint
with an angle grinder and paint removing disk (pan scourer type).
Finish afterwards was an acrylic stone sealer. It's tricky to get the
surface buffed just right, as the disk will smear given half a chance,
but it looks far better now.