Menu Contact Us Downloads Quality Control – Research & Development SIGMA in-house laboratory is equipped with modern apparatus to test both raw materials and finished products in compliance with international reference standards. In addition to this daily quality control, SIGMA highly qualified personnel made up of chemists and geologists guarantee on-going research into product innovation and services offered to improve existing products, develop new grades and satisfy customers’ specific requests. X-ray fluorescence spectroscopy Polarized light microscopy RUL (Refractoriness under load) & Creep in compression X-ray diffraction Ultrasonic testing Apparent porosity & bulk density Via delle Grigne, 12/A 22070 Locate Varesino (CO) - Italy VAT N. 01872290133 Phone +39-0331-823.195 Fax +39-0331-823.198 e-mail: office@sigmaref.it S.I.G.MA. S.R.L. Locate Varesino, Italy SIGMAREF SRLU Plovdiv, Bulgaria REFRATRADE S.R.L. Locate Varesino, Italy