Oxygenating chilled wort greatly reduces lag times between yeast pitching and onset of fermentation. By feeding yeast with concentrated oxygen, fermentation will proceed faster, resulting in lower terminal gravities, less off flavors and esters, by-products and in the end a better tasting beer. Aerating with pure oxygen in 5 – gallons of wort for 1 minute will provide approximately 9 – 10 ppm of dissolved oxygen.
The oils from your skin can clog the microscopic pores. Use latex gloves, a tightly knit cloth or a rag when handling the stone.