# Age and Source of the Jinjingzui Skarn-Type Gold Deposit in the Southeastern Hubei Province, China
## 4 Analytical Results  
### Major Elements and Trace Elements  
The major and trace element compositions of the three diorite samples from the Jinjingzui deposit are listed in Table 1. Low SiO\({}_{2}\) concentrations (54.75-56.66%) were measured, with high concentrations of Fe\({}_{2}\)O\({}_{3}\)\({}^{\mathrm{T}}\) (5.68-8.94%), MgO (2.05-2.19%) and TiO\({}_{2}\) (1.06-1.08%) detected. Al\({}_{2}\)O\({}_{3}\) and CaO content ranged from 17.89-18.05% to 7.64-8.96%, respectively. The alkali content (K\({}_{2}\)O + Na\({}_{2}\)O) was reported from 6.46 to 8.03%. Two samples (JJZ-7 and JJZ-8) plotted in the TAS diagram lie in the monzodiorite area, and one (JJZ-9) in the monzonite region (Figure 8a). The A/CNK ratio of the samples varies from 0.69 to 0.75, indicating a metaluminous composition (Figure 8b). In the SiO\({}_{2}\)-K\({}_{2}\)O diagram (Figure 8c), two samples (JJZ-7 and JJZ-8) fall into the high-K cal-alkaline area and one in the shoshonitic area.  
Samples in this study are rich in large-ion-lithophile elements (LILE), Rb-Ba and high-field-strength elements (HFSE) Th. The samples exhibited subparallel chondrite-normalized REE patterns, characterized by strong fractionation between light and heavy REE, with barely perceptible Eu anomalies (8 Eu = 0.97\(\sim\)1.00) (Figure 9b). The total REE, LREE and HREE content of the samples are 296.97-312.61 ug/g, 272.41-286.65 ug/g and 24.56-25.96 ug/g, respectively (Table 1). LREE/HREE ratios range from 10.68 to 11.09 with the (La/Yb)\({}_{\rm N}\) ratio varying from 18.42 to 19.80.  
\begin{table}
\begin{tabular}{l c c c c c c c c c c c c c c} \hline \hline Sample & SiO\({}_{2}\) & TiO\({}_{2}\) & Al\({}_{2}\)O\({}_{3}\) & TF\({}_{2}\)O\({}_{3}\) & MnO & MgO & CaO & Na\({}_{2}\)O & K\({}_{2}\)O & P\({}_{2}\)O\({}_{3}\) & LOI & Total & Mg\({}^{\rm g}\) & A/CNK & NaO\({}_{2}\) \\  & & & & & & & & & & & & & & & & \\ JJZ-7 & 53.74 & 1.08 & 17.7 & 8.49 & 0.10 & 2.15 & 7.71 & 4.21 & 2.49 & 0.5 & 1.82 & 99.98 & 31.08 & 0.75 & 6.7 \\ JJZ-8 & 52.25 & 1.09 & 17.44 & 8.71 & 0.10 & 2.11 & 8.73 & 4.01 & 2.46 & 0.54 & 2.51 & 99.95 & 30.18 & 0.69 & 6.46 \\ JJZ-9 & 55.22 & 1.06 & 17.6 & 5.53 & 0.06 & 2 & 7.45 & 3.96 & 4.07 & 0.52 & 2.47 & 99.94 & 39.17 & 0.72 & 8.03 \\ \hline Sample & Rb & Ba & Th & U & Nb & Sr & Zr & Hf & Yb & La & Ce & Pr & Nb & Nd & Sm \\ JJZ-7 & 63.12 & 643.36 & 12.88 & 0.17 & 172.2 & 1194.21 & 237.17 & 6.27 & 2.28 & 60.17 & 124.9 & 13.87 & 17.22 & 59.46 & 10.53 \\ JJZ-8 & 62.68 & 657.32 & 13.52 & 0.22 & 17.51 & 1223.91 & 225.37 & 6.04 & 2.29 & 63.21 & 132.12 & 14.67 & 17.51 & 61.71 & 11.21 \\ JJZ-9 & 105.69 & 752.81 & 11.95 & 0.38 & 17.91 & 1087.36 & 220.68 & 6.06 & 2.34 & 60.05 & 127.41 & 14.06 & 17.91 & 59.95 & 10.94 \\ \hline Sample & Eu & Gd & Tb & Dy & Ho & Er & Tm & Yb & Lu & Y & EkRE & 8 Eu & (La/Yb)\({}_{\rm N}\) & & & \\ JJZ-7 & 3.48 & 10.86 & 1.35 & 5.55 & 1.05 & 2.77 & 0.38 & 2.28 & 0.33 & 26.88 & 296.97 & 1 & 18.94 & \\ JJZ-8 & 3.73 & 11.79 & 1.41 & 5.71 & 1.13 & 2.93 & 0.38 & 2.29 & 0.32 & 27.64 & 312.61 & 0.99 & 19.8 & & \\ JJZ-9 & 3.56 & 11.48 & 1.4 & 5.76 & 1.15 & 3.02 & 0.39 & 2.34 & 0.32 & 27.93 & 301.81 & 0.97 & 18.42 & & \\ \hline \hline \end{tabular}
\end{table}
Table 1: Composition of major elements (%), trace elements (ppm), and REE (ppm) of samples from the diorie.  
Figure 8: Chemical classification diagrams for the Jinjingziu diorite: (**a**) Alkalis (K\({}_{2}\)O + Na\({}_{2}\)O) versus SiO\({}_{2}\) diagram [24], the division between alkaline and sub-alkaline is after [25]; (**b**) A/NKversus A/CNK diagram (after [26]), A/NK = n(Al\({}_{2}\)O\({}_{3}\))/[In(Na\({}_{2}\)O) + n(K\({}_{2}\)O)], A/CNK = n(Al\({}_{2}\)O\({}_{3}\))/[In(CaO) +n(Na\({}_{2}\)O) + n(K\({}_{2}\)O)]; (**c**) K\({}_{2}\)Oversus SiO\({}_{2}\) diagram (compositional fields modified from [27]).  
Figure 9: Primitive mantle-normalized trace element spider (**a**) and chondrite-normalized REE pattern diagram for the Jinjingziu diorite (**b**). Echeng diorite in southeastern Hubei data from [PERSON] et.al., 2018 [28].