About Us

PT Kaltara Batu Konstruksi (PT KBK) is a Private Limited Liability Aggregate (Rock) Mining Company incorporated in the Republic of Indonesia. PT KBK holds an Operation Production Mining Business License, known in Indonesian as Izin Usaha Pertambangan Operasi Produksi (IUP OP), which is issued by the Indonesian Investment Coordinating Board (BKPM). KBK’s IUP covers a total area of 40 Hectares (400,000m2) in Malinau, North Kalimantan, Indonesia, close to the Malaysian border.

KBK IUP OP contains a 30-meter high above surface outcrop dome and 120-meter beneath deposit of Graywacke rock aggregate that is to be extracted using drill and blast quarrying methods. Our objective is to safely and cost-effectively meet business requirements through the appropriate management of risks by providing our workforce with a safe working environment.

The name Kaltara Batu Konstruksi stems from:
Kaltara, abbreviation for Kalimantan Utara (North Kalimantan),​
Batu (rock or stone), and​ Konstruksi (construction).​



  • To establish a world-class quarry and become the market leader.
  • mission


    • To contribute to the development of Indonesia.

    Our History

    Our journey began in early 2016 when our founder and President Director, Mr. Josh Sleiman, recognized Indonesia's significant shortage of raw construction materials. This realization inspired our goal: to become the top aggregate materials company. We focused on acquiring greenfield lands with economically viable aggregate products for both domestic and international markets. In late 2016, KBK was established with the purpose of obtaining a Mining Business License (WIUP) for a land area suitable for developing and operating an aggregate quarry. This quarry is situated in Malinau Regency, North Kalimantan.

    Corporate Culture

    An organization is as great as its people, and its people are as great as its culture.
    KBK’s corporate culture is based on the 5T's.
    "Through Truth and Transparency, sincere Trust is
    established, thus allowing the utmost Tolerance for all to Thrive."

    - Josh Sleiman -


    KBK is committed to good corporate governance, which promotes the long-term interests of stakeholders, strengthens board and management accountability, and helps build trust in the company and community.

    The Board is elected by the shareholders to oversee their interest in the long-term health and the overall success of the business and its financial strength. The Board serves as the ultimate decision-making body of the Company, except for those matters reserved to or shared with the shareholders. The Board selects and oversees the members of senior management, who are charged by the Board with conducting the business of the Company.

    The Board of Directors has established Corporate Governance Guidelines, which provide a framework for the effective governance of the Company. The guidelines address matters such as the Board’s mission, Director responsibilities, Director qualifications, and determination of Director independence, Board committee structure, Chief Executive Officer performance evaluation and management succession.

    Organizational Chart