Paper clay is any clay body which has had processed cellulose (usually paper) added to it. There are a few differences from paper clay to normal air dry clay such as the presence of paper fibers, the thickness and stodginess of it and the colour. “White” paper clay is usually a light grey in colour and lightens as it dries. Even when it is fully dry, the colour of the “whiteness” can be questionable.
Price
Paper clay is usually bought in big blocks as opposed to polymer clay, which is usually bought in small quantities. As paper clay is bought in larger blocks, it is considered more cost effective – a 1kg block of paper clay can be bought for around £3 in the UK.
Availability
Paper clay is marketed as “air dry clay” in the UK and therefore is one of the only available types of air drying clay in the UK. One brand is only available in the UK, which is DAS, and can be found in most craft, art and hobby shops as well as stores like The Works and WH Smiths. The same can be said for American and Asian types of paper clay, with the exception of The Works and WH Smiths (as the stores haven’t branched out to the US and Asia, as far as my knowledge goes) and popular brands include Creative Paperclay and Pearl Paperclay.
Uses
Paper clay has many of the same uses as polymer and air dry clay, such as jewellery making, charms, cabochons, beads, creating vessels and sculpting. It can be used in moulds and also to create moulds but the clay will need to be varnished upon drying and some form of release agent (such as baby powder) will be needed. Deco artists tend to use paper clay to make sweets and other cabochons. The texture of paper clay is also useful for sweet deco items such as bread, cake, biscuits, ice cream and cookies.
Texture & Workability
In the UK, air dry clay is surprisingly hard to find, and because of this, a brand of paper clay called DAS is marketed wrongly as air dry clay. Therefore this article may be a little biased due to my lack of experience with other paper and air dry clays as well as troubles with availability. I believe real air drying clay is light, slightly sticking, flexible and workable and bright white in colour. The “air dry clay” available in the UK is a dirty, unbleached grey in colour (even though it is marketed as white) and lightens to a questionable “white” colour as it dries. It is thick and stodgy to pull apart and fibrous and mushy for the texture. You can colour paper clay with the regular substances used for other clays, such as chalk, ink, paint, foil, embossing powder, etc., but it takes a considerable amount of chalk shavings or paint to get a strongish colour. Because the original colour of the clay is a dirty colour to begin with, you get a dirty version of the colour you are aiming for. The clay is quite hard to work with too, with a texture and feel comparable to dumpling dough. It is cold and wet to the touch and has a fibrous, uneven texture and feel to it. It is hard to mould and create even simple shapes and does not take detail very well. Because of the paper fibres, the surface tends to rip, tear and stress when details are applied. As such, this is not a very popular choice to use among jewellers and artists as it also cracks more easily and is uneven in colour compared to other clays. Paper clay doesn’t shrink much, however, and is very light in weight compared to polymer and normal air dry clay.
Curing & Aftercare
Speaking from my experience, when the paper clay fully dried, it had visibly cracked and had a chalky feel to it. It was very hard to the touch and lightweight compared to other clays, however. The “white” colour is more like a very, very, very light grey and can be questioned. Paper clay is usually air dry and dries pretty fast, most items taking around 24-48 hours to completely dry. As with most air dry clays, paper clay dries from the outside in, so you need to leave it a little longer than when it looks completely dry on the outside. In order to dry pieces faster and more consistently, I turned pieces over once a day. You can paint, sand, buff, file, varnish and otherwise treat the clay once used but sometimes the clay absorbs water based substances, causing it to have that wet look again. You can also rubber stamp or use marker pens on this clay whilst dry, but make sure to seal your work afterwards. You can also rework and mould paper clay by adding more water to it before varnishing, allowing it to return to a soft, wet state again. This is a quality that gives it advantage over polymer clay.