The eastern part of Oregon is known for the prolific jasper deposits found there.  There are many varieties and many look alike and can only be distinguished by the very specific characterizations known to the miners and experts within the field.  When possible, the region or name as given by the person from whom the collection was acquired will be noted, however, it is nearly impossible for me to confidently verify every variety.  

Spring Mountain ?

Origin:  Oregon

Dimensions: 3" x 2" and is approximately 7.3 mm thick.  Weight = 54 grams. 

Shown wet.  Not polished.  No known flaws.