First generation pastels had black jewels, whereas second generation pastels were more vibrant colors with colored jewels. Don't confuse the white pen above with a nurse pen. Nurse pens were a longer SJ size with red, green, or black jewels.
Pastel Pens came in what was referred to as a "Petite-Pak". There were several different variations of these. These two are from the orchid and pink sets above.
This is a Nurses pen with green jewels. Probably the hardest to find of the set of three in red, black and green jeweled variants.
Pastels utilized a much softer plastic and are often found with cracks in the cap lip such as this first blue example. These are second generation Pastels with the colored jewels. All have the later spoon style lever.
This is an unusual LJ sized pastel possibly meant as a marketing or giveaway pen. It is quite uncommon to find these larger pastels.