ABSTRACT
The diamond industry has long been associated with environmental and social problems, ranging from mining practices to ethical concerns related to diamond sourcing. In recent years, there has been a growing interest in lab-grown diamonds as a sustainable alternative for diamond consumers. However, the production of lab-grown diamonds has own challenges. This article examines the capital expenditures per annualized carat of rough diamonds obtained through mining and two fabrication methods: high-pressure high-temperature (HPHT) and microwave plasma-assisted chemical vapour deposition (MP CVD). Lab-grown diamonds produced using HPHT and MP CVD methods require significantly higher capital expenditures per annualized carat compare to mined diamonds. HPHT diamonds require on-time CapEx of 500-833 US$ per carat annually, while MP CVD diamonds demand 549-1648 US$ per carat annually. Finding ways to reduce production cost and increase efficiency will be crucial in realizing the potential of lab-grown diamonds as a sustainable alternative to mined diamonds.
ABSTRACT
Diamond is a form of carbon that has been attracting attention for hundreds of years, owing to its physical and chemical properties of hardness, thermal conductivity, chemical inertness, and transparency. Labor and the long-term impact of a diverse workforce, is one of the most important factors in diamond mining and production and must be considered when assessing economic benefits. In the present study, we examined the labor input required to obtain one carat of diamond, via three methods: open-cast mining, high-pressure high-temperature synthesis and 2.45-GHz microwave plasma chemical vapor deposition. We discovered that to produce a carat of (near-) colorless diamond, the labor inputs are approximately 1.83 h and 3.43 h of work using the HPHT and 2.45-GHz MP CVD methods, respectively. We noted a lower labor input of work per carat for the mining of diamonds of assorted sizes and colors from the two main DeBeers diamond fields in Botswana (Orapa and Jwaneng). This paper is based on our observations and public reports, and we think that our findings will be helpful in understanding the labor input per carat for the analyzed methods, understanding the main technological challenges facing the diamond industry that could potentially affect future labor productivity.
ABSTRACT
NaCl is one of the simplest compounds and was thought to be well-understood, and yet, unexpected complexities related to it were uncovered at high pressure and in low-dimensional states. Here, exotic hexagonal NaCl thin films on the (110) diamond surface were crystallized in the experiment following a theoretical prediction based on ab initio evolutionary algorithm USPEX. State-of-the-art calculations and experiments showed the existence of a hexagonal NaCl thin film, which is due to the strong chemical interaction of the NaCl film with the diamond substrate.
