MURRHINA.	191
	Leopold exhibited this Agate to Lamboccius with his own hands, as the most important of all his artistic treasures ; but to him also the miraculous inscription constituted its principal value. The front of the altar in the Chiesa del Jesu, Rome, is formed of a single slab of what the archaeologists there pronounce the long-sought Murrhinum, found in the ruins of an ancient house in the Forum. ' " It answers the de­scription in Pliny very well. It is purple in colour, with strata of a dull white running through it : on the edges of the white there is a slight iridescence. It bears a resem­blance to fluor-spar, but it is not fluor, for, as Sibilio at Rome showed me, fluor-spar is easily scratched, whereas the so-called Murra cannot be scratched, more particularly in the white. This white vein is a pure horn-stone."— (H. M. Westropp.) Brückmann possessed a cameo in a similar composite, one stratum silicious, the other calca­reous. Such a mineral was doubtless classed amongst the Murrhina by the Romans, but, as certainly, did not ex­clusively engross that appellation.