Qualiy of polish?

Being rather new to the skill set i come across basic questions, and continue to not be certian of the quality of polish i am finishing my stones with. I am currently working a small Saphire and have increased my magnification by using 3 times reading glasses and my 14 times hand lens. Thing is on this stone i seem to be incountering numerous small pockets or bubbles on the facets, no scratchs and with 3 time magnification the facets appear to be a little at certain angle but generaly clean. Am i being overly concerned, could it just be a product of the stone quality as it is not as clean a stone as i first thought. Or working a hard material it this a normal progression in polishing and just keep working trough it.

I am using a tin lap with 0.25 micron diamond paste.

Anyone care to share your thoughts. I would post a pic but i am not sure i can capture what i am seeing.