Na2Ca2B4Si4O16OH2

Na2Ca2B4Si4O16OH2 is a chemical formula representing a hydrated sodium–calcium borosilicate. The composition indicates two sodium (Na+) ions, two calcium (Ca2+) ions, four boron atoms, four silicon atoms, sixteen oxide components, and two hydroxyl groups per formula unit. This combination places the material among borosilicate frameworks in which boron and silicon occupy tetrahedral coordination with oxygen.

In structural terms, borosilicate networks typically consist of SiO4 tetrahedra linked with BO4 (and sometimes BO3) units. The Na and Ca cations are expected to reside in interstitial sites within the framework, balancing charge and contributing to the hydration state and overall stability. The exact arrangement of boron units (tri- versus tetra-coordinate) and the detailed crystal structure for this specific stoichiometry are not widely reported, so the precise topology remains undetermined in public literature.

Occurrence and synthesis information for this exact composition are limited. If it exists as a natural phase, it would likely form under specialized hydrothermal, metamorphic, or boron-rich fluid conditions, or alternatively as a synthetic phase in borosilicate research, ceramics, or glass-ceramic contexts. Because detailed physical properties (color, hardness, crystal system, and optical characteristics) are not well established for this exact formula, those attributes are not provided here.

Classification would place this compound among borosilicate minerals or synthetic borosilicate phases, distinguished by a framework of interconnected SiO4 and BOx units with interstitial Na and Ca cations and hydrational OH groups. Further experimental characterization would be required to confirm its crystal structure and properties.