Fifth. They run A, B, Γ, Δ, S. A is recorded in the B.M., B in Spink, Γ, Δ, and S in the Vienna Collection. RIC rates them all scarce.
I was doing a bit of research and this is what I found" Magnus Maximus( 383-388), the tenacious usurper of the West, reduced by one-sixth the weight of Siliqua at Londinium and the Gallic mints to 1.9 grams, and even by more after he occupied Aquileia and Rome (1.5g) And The weight of Light Siliqua was extremely variable. This fact has led some researchers to conclude that there was a 1-1/2 Siliqua later in the Empire after the reform of 355/6. However these pieces are best understood as Siliqua struck to the old standard of 96 to a Roman pound, possibly for donatives or ceremonies. I love history!
Nice siliqua of Valens, this série is with Roset Diadem and some issues with also pearl diadem. But this issue is interresting also for this extraordinary siliqua of valens, struk by the first officina, one of the 3 siliquae with the left bust : VALENS (364-378) - CONSTANTINOPLE - RIC IX 11e(1) ©The Trustees of the British Museum Heavy Siliqua, 364-365, RR A/ D N VALENS-P F AVG Dominus Noster Valens pius Felix Augustus, Notre maître Valens Pieux et Heureux Auguste Buste à gauche drapé et cuirassé, tête diadémée (Perles). R/ VOT/V//CONSA Votis quinquennalibus, Vœux pour le cinquième anniversaire de règne Légende en 2 lignes dans une couronne de lauriers fermée. Argent, RIC IX 11e(1), RSC 87†a Fiche de la monnaie sur la base Siliquae
Sorry, I know nothing about late silver and less about gold. I have a few of the most ordinary siliquae and that is it.