I don't think Lavender is black, but rather self-blue that breeds true, but I understand what you mean by "solid" color.
Genetically, a Lavender is a black bird, with the black changed to a gray shade by the lavender gene. It's the black-all-over part that I think you want to avoid, even if the "black" is then changed to blue, or lavender, or chocolate (3 different genes).
Birchin is basically duck-wing pattern or bb red pattern, correct?
No, not quite.
That chart you've got with the "e" genes shows the difference:
Birchen has E^R while Black Breasted Red (Duckwing) has e+.
The various e genes affect the down color of the chicks, and also affect how the other colors are distributed on the chicken.
Duckwings have e+ the wildtype. That includes Black Breasted Reds and Silver Duckwings, and of course the Red Pyles when you have Dominant White, and various other colors.
The chicks tend to have stripes in their down, sort of like chipmunks.
The hens usually have a salmon breast, and lots of black/gray stippling on their backs.
The roosters are the actual Black Breasted color.
But Sebrights should have E^R, just like Birchens do.
Chicks with e^R usually have a lot of black on them, sometimes with various light markings.
Birchen hens have a lot of black, with silver around the base of their neck.
The roosters have a Black Breast, and look a lot like the duckwing ones, but there's a little difference in the wing coloring so they get called crowwings in some breeds.
I suggested Birchen games because of having e^R, just like the Sebrights.
Solid blacks are E (Extended Black), and so are solid blues and lavenders and mottled, barred, crele, Chocolate. And all of them have various modifiers to avoid silver leakage or gold leakage.
Soooooo, if Birchin is what we're using for silver lace, can I use the corresponding colors of Birchen/duckwing-pattern to create the other lace colours? BB reds to make Golden lace (Black lace, gold), Red Pyles to create buff lace (white lace, buff)?
If you're using Birchen for Silver Laced, then I would expect there to be a similar color in gold--it might be called Gold Birchen or Brown Red. I think Lemon Blue is also based on Gold and Birchen.
I don't know of a Birchen-based color with Dominant White, so you might have to get that gene from a Red Pyle.
I think sorting the Birchen-based colors from the Duckwing colors might be easiest if you look at the hens and the young chicks. The Birchen-based hens will be mostly black, with just a ring of silver or gold around the base of their neck. The Birchen-based chicks will be mostly black too. But the Duckwing hens will usually have a salmon-colored breast, and their backs have a mixture of black and silver or black & gold. The Duckwing-based chicks usually have stripes like little chipmunks.
Of course, gold vs. silver and black vs. blue vs. dominant white can change those a bit: a Blue Birchen hen will be mostly blue instead of mostly black, and a Duckwing-based chick with dominant white (Red Pyle) will have red & white stripes instead of the usual brown & black ones, and so forth.
I thought using partridge Silkies with Silver lace cochins would facilitate lacing, but I guess it would just make for a leaky, messy silver lace.
I think "Gray" Silkies are the silver version of Partridge, so you might be able to use them.
I don't know how bad the leakage would be, because I haven't been able to find much information that tells about that specifically. It's usually just a brief comment when a poster or author is trying to talk about something else. You might be able to get some good silvers in the F2 generation, or it might take many more generations, and I just don't know. I was simply assuming that using only silver birds would save you some effort, just like I'm assuming that using Birchen instead of Duckwing would save some effort by having more genes already "right" for what you want to create.
Have you played with the genetics calculator?
https://kippenjungle.nl/kruising.html
You can change the genes in the dropdown boxes, and see the pictures change.
(It can also be used to calculate offspring from a cross, but I rarely use that feature.)
I think a Birchen would have E^R (Birchen) and S (Silver), and everything else the wildtype form (that's the default setting, and they're all marked with + to make them easy to find again.)
A Sebright should have E^R (Birchen), Co (Columbian), Db (Blacktail or Dark Brown), Pg (Pattern Gene), Ml (Melanotic), and S (Silver.)
And Db, Pg, Ml are linked, so they should usually get inherited together, which will make your project easier. If you've already got the E^R and Silver, you'll just have Columbian and the Pg linkage group bring in, and that should create your single laced pattern.
Of course there are a bunch of modifiers that aren't in the calculator, but that are needed to make it look right, but at least you'll have the basic pattern set at that point. And if you lose Co (Columbian), you'll get Spangled birds--I don't know if you want them, but they might pop up at some point.
Um, that ended up longer than I expected
