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The links between plutonic and volcanic systems are still debated. If a connection exists, then some middle- to upper-crustal intrusive systems should be partial cumulates. A version of this debate is ongoing in the normally zoned, late-Cretaceous, Tuolumne Intrusive Complex (TIC) which was emplaced incrementally over ~ 10 m.y. Some authors have proposed that incremental construction took place by the emplacement of small volumes of magma that do not interact with each other whereas others have argued that magmas are emplaced during high magma addition rate events where larger magma chambers develop that are capable of crystal-liquid separation, magma mixing, and crystal recycling. This study utilizes hornblende (Hbl) and titanite (Ttn) compositional zoning patterns and mineral-melt equilibrium relationships to assess the importance of crystal-liquid separation and other magmatic processes operating at the level of emplacement. The initiation of hornblende (Hbl) crystallization in the TIC is early (~ 810–860°C), whereas titanite (Ttn) is a more moderate to lower temperature phase that crystallized at temperatures below ~ 760°C. \nHornblende-melt Fe/Mg partitioning relationships and hornblende chemometry indicate that the majority of Hbl from the TIC (and other calc-alkaline intrusions) is not in equilibrium with associated bulk-rock compositions and that bulk-rocks instead typically represent partial cumulates. Hornblende chemometry suggests that most Hbl is in equilibrium with rhyolitic melt compositions and that only small distinctions can be made between the calculated melts from each of the units. Therefore, the TIC is interpreted to have largely developed through emplacement of dacitic to rhyolitic magmas that underwent crystal-liquid separation (i.e. crystal accumulation and/or melt loss) at the level of emplacement. The more mafic bulk-rock compositions likely reflect greater extents of crystal accumulation and/or melt loss, such that the most melt-like samples occur in the felsic interior of the TIC (e.g. Cathedral Peak). Presumably, these ~ rhyolitic magmas were sourced from lower crustal depths in melting, storage, assimilation, and homogenization or ‘MASH’ zones (Hildreth and Moorbath, 1988) or in ‘hot zones’ (Annen et al., 2006). Hornblende and Ttn trace element compositions suggest that the maximum abundances of high-field strength elements in Kuna Crest and equigranular Half Dome magmas was higher than in porphyritic Half Dome and Cathedral Peak magmas. Thus, a major change in the trace element compositions of magmas that were generated at depth is inferred to have occurred prior to emplacement of porphyritic Half Dome magmas. \nThe compositional zoning patterns of Hbl and Ttn support fractional crystallization, magma mixing (+ thermal rejuvenation), and lower temperature (< 750°C) dissolution-reprecipitation processes. Where compositional evidence is suggestive of magma mixing, mixing is interpreted to have occurred between magmas of similar temperature and of similar major and trace element composition (i.e. between silicic magmas). The similarity of magma compositions and the effects of magma mixing make it challenging to 1) identify distinct magma bodies and 2) recognize recycling of crystals within and between units. However, the least fractionated REE patterns of Hbl and the Gd vs SmN/YbN signatures of Ttn may be distinctive between samples and may therefore be useful for inferring crystallization from distinct magma bodies. In general, the least fractionated Hbl REE patterns within a sample display similar shapes, indicating that where intracrystalline zoning patterns can be used to support magma mixing processes, mixing commonly occurs between magmas of similar composition. Furthermore, the least fractionated Hbl REE patterns may be distinctive between samples, indicating crystallization from distinct magma bodies. Hornblende with similar REE patterns may be separated by several km (~ 5 km), potentially indicating that the size of individual magma bodies was large. However, Hbl with distinct REE patterns may also be recognized at scales of < 1 km. Titanite also records evidence supporting fractional crystallization, magma mixing and/or thermal / redox changes, and dissolution-reprecipitation. Where strong evidence for mixing occurs, the compositional data support mixing between magmas of similar composition. Alternatively, these data could be interpreted to reflect thermal and/or redox changes that led to dissolution followed by reprecipitation. Titanite from each of the lithological units is characterized by distinct Gd vs SmN/YbN signatures, suggesting that if magma mixing was important, then mixing occurred between magmas of similar composition, or before Ttn crystallized. These distinct signatures indicate that either magma mixing typically occurs prior to Ttn crystallization or that Ttn is highly susceptible to dissolution during heating related to large scale magma mixing events. The distinct Gd vs SmN/YbN signatures and the presence of Ttn in phases that may be less susceptible to dissolution during mixing events (e.g. plagioclase, K-feldspar, and Hbl) may provide targets for future analysis aimed at assessing the extent to which Ttn from Kuna Crest and equigranular Half Dome magmas were recycled into porphyritic Half Dome and Cathedral Peak magmas.