[NB: I'm missing a few pictures that I thought I took, so there are a few blank spaces. I should have filled them in by Tuesday.]
Bobbin lace is great. Once you've seen it a few times, it's immediately recognizable because it's so clear. Every thread's path is traceable, and each one gets used actively (rather than being a passive warp all the way down). The two pictures below are shown sideways to the direction they were made.
In filet lace, the maker first creates a knotted net with a square mesh. Then the motifs are filled in by weaving with a needle and thread. Like bobbin lace, you can follow the threads' paths with your eyes. The knots in the net are also an important identifier, as machines can't replicate them well.
Tape lace is created with premade - either machine-made or bobbin - tapes, which are basted down to a piece of fabric or board in the desired shape. Then the brides (pronounced "brids") are strung between them to sew them together. This was a fairly popular craft around the turn of the twentieth century.
For the most part, knitted lace is recognizable because it's done in garter stitch. Historically, anyway. It also tends to not be as lacy and open as other types of edgings, but for the most part: if you understand what knitting looks like on a small gauge, you can spot it. L. M. Montgomery mentions it in Anne of Green Gables:
Sophia Sloane offered to teach her a perfectly elegant new pattern of knit lace, so nice for trimming aprons.
Because of crochet's versatility, three examples of crocheted lace can look completely different. One the one hand, you have lace that, like knitted lace, uses the method with a fine thread and ordinary techniques. It looks a bit like granny squares.
On the other hand, you have crocheted filet lace imitation, where flat motifs are created against a background of chain-stitched squares that look sort of like the net. You can see the chains in the net, though, and of course there are no knots.
On the third hand, there is Irish crochet. In this method, individual motifs are crocheted (sometimes three-dimensionally) and then joined with crocheted chains that imitate the thorned (picoted) brides of tape lace.
Reticella Needle Lace
One of the older types of needle lace, reticella is performed by creating a grid of base threads - either by pulling out (or cutting) the ones in between, or by laying down threads by hand. More threads are strung between the gridlines to create motifs, and these are all thickened with buttonhole stitching. Solid areas are filled in with tight, close loops. Other types of needle lace with less geometric bases took over for use in clothing by the eighteenth century, but it made a slight resurgence as a craft in the early twentieth century.
This isn't very common; I think it was mostly popular in the early twentieth century, as a craft or a souvenir. Each motif is made separately by stringing spokes through a circle and weaving around them with a needle. You tend to see it on household linens rather than clothing.
I've tried to do tatting and found it very confusing, but it's easy to spot. It's created in linked circular motifs, often with picots. Generally, it's seen on mid-Victorian pieces.
An imitation of bobbin lace, and a pretty good one. Because of the way the machine's bobbins work, you can generally follow the paths of the threads. However, a) if you put it up next to a piece of genuine bobbin lace, it will look shoddy and fake and like the tension is out of whack, and b) in areas of half-stitch ground, bobbin lace will have threads running in both diagonals and horizontally, while Barmen lace will have diagonals and verticals. In general, machine laces rely on vertical warps while hand-made ones don't.
Schiffli Chemical Lace
The Schiffli machine is essentially a sewing machine that was used to embroider fabric commercially. The lace pattern would be sewn on a special material that could be dissolved without harming the stitches, and then that's exactly what would happen. Sometimes, outlines are sewn around a non-dissolvable fabric, often for petals and such, or it's used to create eyelets. The main thing about recognizing it is that it always looks a bit fuzzy and indistinct.
This is also a chemical lace, but a nicer one. It doesn't have the same fuzziness as Schiffli, and it's not always satin-stitch - solid areas look woven, I'm not sure how it works.
There are a lot of other machine laces, but they're pretty obvious so I won't go into them (also, I don't tend to take pictures of them when I see them because they're not as interesting). But if you'd like a more serious treatment of the subject, Pat Earnshaw's Identification of Machine Laces is very thorough, as is this booklet from the Dress and Textile Specialists and V&A, Identifying Handmade and Machine Lace.
I have a few exciting posts to make this week - I'm going to try to type them up this weekend and space them out during the week, since I don't get much of a chance to blog then but I surely can hit "Publish". I want to drop intriguing hints but they all give the game away, so - stay tuned!