Analisis Quality Control Terhadap Perubahan Kadar Nikel (Ni) Dari Front Penambangan Ke Stockpile Serta Dampaknya Terhadap Ekonomi Perusahaan Studi Kasus PT Riota Jaya Lestari Kecamatan Lasusua, Kabupaten Kolaka Utara, Provinsi Sulawesi Tenggara

Anita Fauziah Widiyanti (Institut Teknologi Adhi Tama Surabaya)
Dewi Pertiwi (Institut Teknologi Adhi Tama Surabaya)
Yudho Dwi Galih Cahyono (Institut Teknologi Adhi Tama Surabaya)

Prosiding Seminar Nasional Teknologi Industri Berkelanjutan
Prosiding SENASTITAN Vol. 06 2026

Riota Jaya Lestari Ltd. is a laterite nickel mining company located in North Kolaka Regency, Southeast Sulawesi, Indonesia, that implements quality control procedures to maintain the quality of its nickel ore production. This study aimed to evaluate ore quality at the mining face and stockpile, quantify changes in nickel (Ni) grade during material handling, identify the factors influencing grade variation, and assess their economic impact on the company. A quantitative approach, incorporating descriptive statistical analysis, was employed. Nickel assay data were processed using Microsoft Excel and presented in the form of tables and graphs illustrating grade distribution, grade deviation, and economic evaluation. PSI (grab sampling) was applied at the mining face, while truck sampling was conducted at the stockpile. The results showed that the average nickel grade at the mining face was 1.56% Ni, whereas the average grade at the stockpile increased slightly to 1.58% Ni, with an average grade deviation of 0.081%. Among the 35 paired samples analyzed, 23 samples exhibited an increase in nickel grade, 10 samples showed a decrease, and 2 samples remained unchanged. All analyzed samples contained nickel grades above the company's cut-off grade (COG) of 1.10% Ni, indicating that the ore remained economically viable for processing. Grade variation was primarily influenced by the heterogeneous nature of laterite nickel deposits, potential ore dilution during ore extraction, unplanned blending practices, differences in sampling methods, contamination during loading and hauling operations, and suboptimal sample preparation procedures. These findings indicate that comprehensive quality control should be implemented throughout the ore handling process to minimize grade variation from the mining face to the stockpile. Based on the observed grade changes, the company achieved an estimated additional profit of IDR 1,473,800,018.01, while grade reductions resulted in an estimated economic loss of IDR 637,889,152.05. Keywords: Laterite nickel, quality control, nickel grade, sampling, stockpile, grade control.