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Debasement of silver Roman coins is a well-known phenomenon and understanding the quality of ancient silver coinages can provide an idea about the underlying fiscal condition of the issuing states. These coins are made from a silver-copper alloy, the surfaces of which were deliberately enhanced at the mints by a process of surface-enrichment to give them the appearance of being made of pure silver. Therefore, any surface analysis would provide a composition of the silver-copper alloy that would not be representative of the original alloy from which the coin blank was made, the result would be too high in silver. However, the bulk of the sample, the interior, should provide a composition that is true to the original alloy. Elemental analysis using negative muons has been used to provide a depth dependent compositional, completely non-destructive analysis of a silver-copper alloy denarius of the empress Julia Domna datable to 211&ndash, 217 CE. The composition of the coin, beyond the surface enrichment layer, is 51 &plusmn, 1.8 % copper and 49 &plusmn, 1.9% silver, taken at a muon depth of 402 &plusmn, 61 &micro, m. The surface enrichment layer is approximately 190 &micro, m thick.

We have studied the heat capacity of a single crystal PrCoAl4. The data indicate that Pr3+ in this compound has a non-magnetic singlet ground state. The compound becomes antiferromagnetically ordered below the Neel temperature of 17 K. The magnetocrystalline anisotropy in PrCoAl4 is relatively strong. Up to 300 K, the entropy contained in the specific heat is 15.2 J/Kmol, which is only 83% of 18.3 J/Kmol expected for the 2J+1-fold degeneracy of the ground multiplet of the Pr3+ ion.

We describe small-angle neutron scattering (SANS) studies of vortex structures in the high T c superconductor YBa 2 Cu 3 O 7 in the mixed state. The SANS technique is a unique tool for probing the crystallography of a flux line arrangement in the bulk sample that can measure the values of the characteristic lengths and the effect of defects on lattice arrangement and orientation extremely accurately. The effects of crystal anisotropy on the field distribution in a vortex line is the topic of this paper