New occurrences of derbylite, Fex2+Fe3+4–2xTi4+3+xSb3+O13(OH), and graeserite, Fex2+Fe3+4–2xTi4+3+xAs3+O13(OH), have been identified in the Monte Arsiccio mine, Apuan Alps, Tuscany, Italy. Derbylite occurs as prismatic to acicular black crystals in carbonate veins. Iron and Ti are replaced by V (up to 0.29 atoms per formula unit, apfu) and minor Cr (up to 0.04 apfu). Mössbauer spectroscopy confirmed the occurrence of Fe2+ (up to 0.73 apfu), along with Fe3+. The Sb/(As+Sb) atomic ratio ranges between 0.73 and 0.82. Minor Ba and Pb (up to 0.04 apfu) substitute. Derbylite is monoclinic, space group P21/m, with unit-cell parameters a = 7.1690(3), b = 14.3515(7), c = 4.9867(2) Å, β = 104.820(3)° and V = 495.99(4) Å3. The crystal structure was refined to R1 = 0.0352 for 1955 reflections with Fo > 4σ(Fo). Graeserite occurs as prismatic to tabular black crystals, usually twinned, in carbonate veins or as porphyroblasts in schist. Graeserite in the first kind of assemblage is V rich (up to 0.66 apfu), and V poor in the second kind (0.03 apfu). Along with minor Cr (up to 0.06 apfu), this element replaces Fe and Ti. The occurrence of Fe2+ (up to 0.68 apfu) is confirmed by Mössbauer spectroscopy. Arsenic is dominant over Sb and detectable amounts of Ba and Pb have been measured (up to 0.27 apfu). Graeserite is monoclinic, space group C2/m, with unit-cell parameters for two samples: a = 5.0225(7), b = 14.3114(18), c = 7.1743(9) Å, β = 104.878(3)°, V = 498.39(11) Å3; and a = 5.0275(4), b = 14.2668(11), c = 7.1663(5) Å, β = 105.123(4)° and V = 496.21(7) Å3. The crystal structures were refined to R1 = 0.0399 and 0.0237 for 428 and 1081 reflections with Fo > 4σ(Fo), respectively. Derbylite and graeserite are homeotypic. They share the same tunnel structure, characterised by an octahedral framework and cuboctahedral cavities, hosting (As/Sb)O3 groups and (Ba/Pb) atoms.

新出现的德贝石，Fe x 2+ Fe 3+ 4–2 x Ti 4+ 3+ x Sb 3+ O 13（OH）和方沸石，Fe x 2+ Fe 3+ 4–2 x Ti 4+ 3+ x在意大利托斯卡纳Apuan阿尔卑斯山的Monte Arsiccio矿山中发现了As 3+ O 13（OH）。钙铁矿在碳酸盐矿脉中以针状黑色晶体的棱柱形出现。铁和钛被V（每个配方单元最多为0.29个原子，apfu）和次要Cr（最多为0.04apfu）代替。Mössbauer光谱证实了Fe 2+的存在（最高0.73 apfu），以及Fe 3+。Sb /（As + Sb）原子比在0.73和0.82之间。次要的Ba和Pb（最高0.04 apfu）替代物。Derbylite是单斜晶系，空间群P 2 1 / m，晶胞参数a = 7.1690（3），b = 14.3515（7），c = 4.9867（2）Å，β= 104.820（3）°和V = 495.99 （4）3。对于1955年的反射，将晶体结构细化为R 1 = 0.0352，F o >4σ（F o）。斑岩在碳酸盐岩脉中呈棱柱状到平板状黑色晶体，通常成对缠绕，或在片岩中以成卟啉状存在。第一种组合中的方铅矿富含V（最高0.66 apfu），第二种组合中的V贫乏（0.03 apfu）。与微量Cr（最高0.06 apfu）一起，该元素替代了Fe和Ti。莫斯鲍尔光谱法证实了Fe 2+（最高0.68 apfu）的存在。砷比Sb占主导地位，并且已测量出可检测的Ba和Pb量（最高0.27 apfu）。花岗岩是单斜晶，空间群C 2 / m，具有两个样品的晶胞参数：a = 5.0225（7），b = 14.3114（18），c = 7.1743（9）Å，β= 104.878（3）°，V= 498.39（11）埃3 ; 和一个= 5.0275（4），b = 14.2668（11），C ^ = 7.1663（5）β= 105.123（4）°，V = 496.21（7）3。分别将428和1081反射的晶体结构细化为R 1 = 0.0399和0.0237，且F o >4σ（F o）。Derbylite和graeserite是同型的。它们共享相同的隧道结构，其特征是八面体框架和立方八面体腔体，其中包含（As / Sb）O 3基和（Ba / Pb）原子。