The online scanning measurement of silicone basis weight on release paper has been a great challenge as the coating basis weight is typically only in the range from 0.5 to 3 g/m2 (0.3 to 2 lbs/ream). Until recently, online sensors for silicone measurement have not been reliably accurate, or have required prohibitively high levels of on-site technical support. A new sensor developed in 2013 employs a high-resolution grating spectrometer in the near infrared spectrum to measure silicone coatings down to 0.25 g/m2 (0.15 lbs/ream) as part of an industrial scanning web gauging system. This new sensor does not require any intensive maintenance or specialized on-site expertise. Technical details of the sensor design as well as long-term field results are presented.