Purple cloth was very expensive. The reason it was so costly was that it was difficult to make. The dye for the cloth came from a shellfish. Purple dye had to be gathered drop by drop from the veins of certain shellfish found only in this area of the Mediterranean.
The little bit of juice was white while it was in the veins of the fish, but when it was exposed to the sun, the liquid changed into bright purple and red colors. It took thousands of seashells to make a yard or two of purple cloth. It took a lot of work to catch enough shellfish to dye even one garment. It was a statement of status, power, and wealth in Roman times.
The beautiful cloth was mainly used by members of the royal families and Roman senators who were required to have a purple band around the edge of their togas, or robes.
(This info gathered over years of research, and I do not know exact origins.)
You can find all the Acts worksheets here:
Visual Aids:A beka: PB 1.1,2,3,4 (This is the number you see in light blue at the beginning of the paragraphs.) There are also (pictured) free visual aids here: http://www.dsmedia.org/resources/illustrations/sweet-publishing
(Original publisher http://SweetPublishing.com)