Global Weighting Agents Market By Type (Barite Weighting Agents, Hematite Weighting Agents, Calcium Carbonate Weighting Agents, Siderite Weighting Agents, Ilmenite Weighting Agents, and Others), By Application (Invert Emulsion, Water Base Drilling Fluids, Completion Fluids, and Others), By Region, and Key Companies - Industry Segment Outlook, Market Assessment, Competition Scenario, Trends and Forecast 2020-2029