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Supplementary Table S3.3. 79 analyses with discordance > 5% have been discarded. The Whetherill Concordia plot (Fig. 10e) shows a string of ellipses representing concordant ages (<5% discordant) from 655 ± 29 Ma (Ediacaran) to 520 ± 23 Ma (Lower Cambrian). Several clusters are observed at 638 ± 10 Ma (n = 5; MSWD = 1.6), 601 ± 5 Ma (n = 21; MSDW = 3.9), 575 ± 2 Ma (n = 76; MSWD = 1.4) and 541 ± 5 Ma (n = 18; MSWD = 0.45), which is suggested to be the best approximation to the crystallization age (Fig. 10f) of this rock. Only one younger analysis (491 ± 22 Ma) falls outside the boundaries of uncertainty of the youngest cluster. 5.2.4. Metagranite of the Valverde metaigneous complex (VALVMIC metagranite) Zircons from this sample display a broad variety of morphology and size, from round and stubby, to thin and elongated and also fragments. Zircons with a homogeneous domain are poorly lumi- nescent. Some grains show complex sector zoning with an inher- ited core. A few grains contain inclusions and likely metamorphic overgrowths (Fig. 9). U-content ranges from 0.75 to 1589 ppm and the Th/U ratio shows a wide variation ranging between lower than 0.1 to 0.79. A total of 193 analyses were performed on 167 zir- Fig. 9. Cathodoluminiscence images of zircons analysed in metagranites from Valverde Metaigneous Complex. VALMIC metagranite and VALMIC1 metagranite samples correspond to the internal sections and the deformed external section of the igneous body, respectively. 206Pb /238U ages are shown. Numbers of the analyses appear in black. Red and green circles represent concordant and discordant analyses, respectively. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.) E. Rojo-Pérez, U. Linnemann, M. Hofmann et al. Gondwana Research 109 (2022) 89–112 The Ediacaran arc section