A polished stone axe and a stone adzehead, both of porphyritic andesite, from the Lambay Island axe factory, circa 3,600–2,500 BC, now in the National Museum of Ireland on Kildare Street, Dublin.
Kinda cheating here a bit as I didn’t actually visit the site – visiting strictly by invitation only. Lambay is meant to be rich in neolithic heritage – the site of an axe factory. Love to go there some day.