It is somewhat unusual for synthetic chemists to employ two different metal salts for the formation of homometallic cluster compounds containing paramagnetic 3d metals, since the anions are often considered solely as charge balancing moieties rather than structure-directing agents. This observation has certainly prompted us to re-examine a number of reactions to probe whether it may be of general applicability, or if it is of more limited scope. Here, the use of both FeCl3, Fe(ClO4)3•6H2O with teaH3 in a high temperature, high pressure reaction leads to the formation of an aesthetically pleasing [Fe15] cage conforming to a centred, tetrakis hexahedron. The high symmetry of the metallic skeleton leads to the presence of competing antiferromagnetic exchange interactions and spin frustration. Use of the finite temperature Lanczos method allows for "an order of magnitude" estimation of the exchange constants present, a computationally non-trivial task for a molecule containing fifteen S = 5/2 spins. Values of Jcube = -17.4 cm -1 , Jpyramid = -17.4 cm -1 , Jc,cube = -17.4 cm -1 and Jc,pyramid = -3.5 cm -1 are consistent with parameters obtained from DFT calculations which fall in the range |J| = 4.6-16.4 cm -1 , and with low temperature heat capacity data which reflects the presence of a large density of low-lying spin states. FeCl3 (0.162 g, 1 mmol) and Fe(ClO4)2•6H2O (0.254 g, 1 mmol) were dissolved in methanol (25 cm 3 ). Triethanolamine (0.198 cm 3 , 1.5 mmol) was added dropwise to the orange solution. Triethylamine (0.418 cm 3 , 3 mmol) was added dropwise and the darkened solution was stirred at room temperature overnight. The dark orange solution was then filtered under gravity and 12.5 cm 3 samples of the filtrate were transferred to Teflon-lined autoclaves and heated to 100°C for 24 hrs. the reaction vessels were left to cool and stand for 48 hrs yielding dark red rod-shaped crystals suitable for X-ray Diffraction. Yield =0.096 g [0.041 mmol] (31.5% by Fe). Elemental analysis (% C H N) calculated (found) for C48H96Cl8Fe15N8O38: C 24.9 (24.35), H 4.18 (4.28), N 4.84 (4.40).