The next phase of the work was the exploration of the Ba-Y-Sn-O system using suspensions of BaCO3, SnO2 and Y2(C2O4)3 (yttrium oxalate). Yttrium oxalate was used after initial trials with Y2O3 showed that the suspensions thickened during storage and became unworkable after a few days. The exploration generated data for 48 compositions at four temperatures (192 individual pellets) in 3 weeks; the researcher was engaged in other tasks during this period. This initial set of trials did not locate any previously unknown phases, but did reproduce the BaY0.5Sn0.5O2.75 quaternary phase reported by Wang et al. To further test the described protocol the quaternary solid solution BaYxSn1-xO3-x/2 was explored in more detail, in particular to investigate whether x = 0.5 was indeed the upper limit of solid solution as is reported. To do this only required two suspensions: an equimolar mixture of BaCO3 + SnO2 and an equimolar mixture of BaCO3 + Y2(C2O4)3. Four sets of 10 discs of compositions of BaYxSn1-xO3-x/2 with x = 0 and 0.5 ≤ x ≤ 0.95, were produced using the workflow and calcined at temperatures of 1200 °C, 1300 °C, 1400 °C and 1500 °C (one set of discs for each temperature, making a total of 40 samples). X-ray diffraction data from 2θ = 10° -52° (d = 4.0 to 0.8 Å) were collected and analysed using TOPAS-academic version 7 software. All of the samples showed a cubic BaSnO3 like phase. The unit cell sizes for this cubic phase are shown in Fig. for a set of samples calcined to 1400 °C for 8 hours. The unit cell parameters that we present here (Fig. ) are reassuringly similar to the data published by Wang et al for x ≤ 0.5 when plotted against the composition values measured through ICP analysis of the freeze dried mixtures, with a precise match for BaSnO3 (x = 0) giving a = 4.11762(9) Å compared to literature value of 4.117 Å. The data show the expected increase in unit cell size with increasing x up to x ≈ 0.56, where the lattice parameter a = 4.2582 (11) Å for the sample with measured x = 0.56, consistent with Vegard's law, which reaches a plateau at x ≈ 0.6. Previously, BaYxSn1-xO3-x/2 phases with x ≤ 0.5, with a maximum lattice parameter for x = 0.5 of a = 4.241 Å, were reported from a sol-gel route with serial synthesis and characterisation of individual samples. Here we extend the solid solution beyond the limit previously reported, identifying the composition BaY0.56Sn0.44O2.72 as the upper limit of the solid solution limit of the solid (Fig. ). This demonstrates that the high-throughput workflow that enables rapid access to a broad range of compositions can reproduce quaternary samples and results produced individually. Removing the samples from the resin and collecting serial diffraction data incorporating a LaB6 internal standard (Fig. ) validated the results from the screening X-ray diffraction and the extension of the solid solution to x = 0.56, demonstrating the reliability of the workflow in identifying new compositions based on diffraction from arrays.