Quarterly report pursuant to Section 13 or 15(d)

Investments in Affiliated Companies - Ownership Percentage (Details)

v3.19.2
Investments in Affiliated Companies - Ownership Percentage (Details)
Jun. 30, 2019
PQ Silicates Ltd.  
Schedule of Equity Method Investments  
Ownership percentage 50.00%
Zeolyst International  
Schedule of Equity Method Investments  
Ownership percentage 50.00%
Zeolyst C.V.  
Schedule of Equity Method Investments  
Ownership percentage 50.00%
Quaker Holdings  
Schedule of Equity Method Investments  
Ownership percentage 49.00%
Asociacion para el Estudio de las Tecnologias de Equipamiento de Carreteras, S.A. (“Aetec”)  
Schedule of Equity Method Investments  
Ownership percentage 20.00%