In my travels across the many blogs and web sites that cover almost anything from the pre-1000 years eras, I came across one that showed the handmade sewing tools reconstruction of a seamstress from the 900AD era. Included in that ancient sewing basket was a glass ball with one side flattened. It was used with a large lap-sized board to press the linen fabric. In this instance, the person doing the reconstruction had a glass blower make her one… alas.. I don’t know any glass blowers…
So I did some checking and experiments and found that using a flat rock will work just as well for pressing seams open when using cottons or linens. (They will not work for smoothing entire pieces of fabric…so don’t throw away your irons just yet!) I had some black tumbled rocks that you put into fish aquariums or crystal vases. When I looked through them I found several that had flat sides and were small enough to put into a sewing bag.
I compared several and found that the actual size of the rock didn’t matter as much as the flatness of the side you will using. A larger rounded rock did not make the crease as crisp and nice as the flatter rock. In the photos I used a piece of cotton quilting fabric to test the creases. Knits, wools, jerseys and most of the synthetics did not respond as well to the rock ironing as the cotton (and I’m sure linen) do.
This would be a wonderful inclusion for any sewing box used to hand sew quilt blocks… paper piecing, etc. It would be good for the sewing done as you commute on trains, planes … waiting in waiting rooms… in the car on short or long trips… or even in the easy chair while working in the evenings watching tv.