Tourmaline has two different [6]-coordinated sites, the Y site and the Z site. Vacancies were reported from both sites. Based on high-quality chemical and single-crystal structural data it usually needs increasing proportions of short-range order configurations Na(Al₂□)Al₆(BO₃)₃[Si₆O₁₈]^V(OH)₃^W(OH) or Na(Al₂□)Al₆(BO₃)₃[Si₆O₁₈]^V(OH)₃^WF in order to produce Y-site vacancies (with □ being the symbol for a vacant site). Less commonly, the short-range configuration Ca(Al₂□)Al₆(BO₃)₃[Si₅T³⁺O₁₈]^V(OH)₃^W(OH) could occur in Al-rich tourmalines with a Si deficiency, where T³⁺ = B, Al. Therefore, tourmalines enriched in cations with charge 2 + (Fe²⁺, Mn²⁺, Mg) contain only insignificant Y-site vacancies. Aluminum-rich tourmalines with ≥ 7.0 apfu Al_total that usually contain ≥ 0.2 apfu Li may have significant vacancies at the Y site. However, no more than 12% vacancies (0.36 pfu) at the Y site can be observed in such samples. If no chemical data for Li is available it is proposed to calculate the Li content in such colourless or coloured tourmalines (elbaite, fluor-elbaite, fluor-liddicoatite, rossmanite) for Y = 2.8 apfu or for Y + Z + T = 14.8 apfu, because this calculation should give more accurate results than calculating the Li content as the difference to 3.0 apfu at the Y site. For Fe²⁺-rich and Mg-bearing tourmalines from the schorl-dravite series with MgO > 1.0 wt% (and only minor amounts of Fe³⁺, Cr³⁺ and V³⁺) the structural formula can still be calculated for Y + Z + T = 15 apfu, because such tourmalines do not appear to contain significant Y-site vacancies. It can further be concluded that the Z site could be only ≤ 1% vacant and therefore such vacancies would be insignificant even in Al-rich tourmaline.

电气石有两个不同的 [6] 配位位点，Y 位点和 Z 位点。两个站点均报告了职位空缺。基于高质量的化学和单晶结构数据，通常需要增加短程有序构型的比例 Na(Al ₂ □ )Al ₆ (BO ₃ ) ₃ [Si ₆ O ₁₈ ] ^V (OH) ₃ ^W (OH )或Na(Al ₂ □ )Al ₆ (BO ₃ ) ₃ [Si ₆ O ₁₈ ] ^V (OH) ₃ ^W F 以产生Y位空位(其中□是空位的符号)。不太常见的是，短程构型 Ca(Al ₂ □ )Al ₆ (BO ₃ ) ₃ [Si ₅ T ³⁺ O ₁₈ ] ^V (OH) ₃ ^W (OH) 可能出现在缺 Si 的富铝电气石中，其中 T ³⁺ = B, Al。因此，富含带电荷 2+ 的阳离子（Fe ²⁺、Mn ²⁺、Mg）的电气石仅包含微不足道的 Y 位空位。 Al_总量≥ 7.0 apfu 且通常含有≥ 0.2 apfu Li 的富铝电气石可能在 Y 位具有显着的空位。然而，在此类样品中观察到 Y 位点的空位不超过 12% (0.36 pfu)。如果没有可用的 Li 化学数据，建议计算此类无色或有色电气石（锂辉石、氟锂辉石、氟锂锂辉石、罗斯锰矿）中的锂含量，Y = 2.8 apfu 或 Y + Z + T = 14.8 apfu ，因为这种计算应该比计算 Y 位点处 3.0 apfu 的 Li 含量的差值给出更准确的结果。对于MgO > 1.0 wt%（且仅有少量 Fe ³⁺、Cr ³⁺和 V ³⁺ ）的 schorl-dravite 系列中富含Fe ²⁺和含 Mg 的电气石，结构式仍可计算为 Y + Z + T = 15 apfu，因为此类碧玺似乎不包含显着的 Y 位空位。可以进一步得出结论，Z 位只能有 ≤ 1% 的空位，因此即使在富铝碧玺中，这种空位也是微不足道的。