Chemical analyzes and observations give new information on the formation of the Sc-silicate thortveitite in the Evje-Iveland pegmatite field. A correlation between a muscovite- or biotite dominated pegmatite and the occurrence of thortveitite may indicate that temperature explain why thortveitite is only found in biotite-rich pegmatites in Evje-Iveland. Biotite start to form at higher temperatures than muscovite, the partitioning of Sc between muscovite and biotite (Yang and Rivers, 2000) and the crystallization temperature of pegmatite quartz in Evje-Iveland (Müller et al., 2015). Chemical analyses on garnets from pegmatites in Evje-Iveland indicate fractionation-trends in the pegmatites. These trends covers the pegmatites from the least fractionated Steli, with a Mn/(Fe+Mn)-ratio of 0.38, to the fractionated Røykkvartsbruddet pegmatite with a Mn/(Fe+Mn)-ratio of 0.97. Pegmatites usually become more fractionated as one moves away from the magmatic or thermal surce (Cerny, 1991a). This is not the case for the pegmatites in Evje-Iveland, which show no regional zoning when it comes to fractionation. Some of the pegmatites are primitive members of the niobium-yttrium-fluorine (NYF)-family, while others are characterized as mixed NYF and litium-cesium-tanatlaum (LCT)-pegmatites in which of they contain a replacement zone with a LCT-component (Müller et al., 2015). The Mn/(Fe+Mn)-ratio, along with the Y and REE content, in the core and rim of a garnet and comparison of averages of the mentioned chemistry between several garnets from different zones in a pegmatite, helps in identifying the presence of a LCT-replacement zone. A good example of the latter is the Solås pegmatite, in which garnets from the wall zone have a Mn/(Fe+Mn)-ratio of 0.6 and 0.9 and Y content of 0.031 and 0.07 apfu, while a garnet from the replacement zone has a Mn/(Fe+Mn)-ratio of 0.98 and Y content of 0.0028 apfu. While the garnets from the wall zone show a normal enrichment of the HREEs, the garnet from the replacement zone shows a drop in the HREE-enrichment. Garnets from other pegmatites that have similar results as those from Solås, can indicate the presence of a replacement zone that is not yet excavated, such as the Hovåsen pegmatite at Eptevann.