Unusual Etch on a Moro Blade

[Spunjer]

all the years i've tried etching moro blades i finally honed a certain technique in which i can bring out the lamination; visibly obvious, yet subtle enough so as not to overtake the overall aesthetic of the blade. good examples are these barungs.
i use the usual stuff: dishwashing soap and acetone to strip the oil, then vinegar and baking soda. after achieving the desired etch, i would run hot tap water on the blade to thoroughly was off any chemicals left on the blade.

[Spunjer]

and then this happened...
i was etching this kris as i thought i saw some squiggly lines along the edge. after spending an hour applying vinegar with a stiff nylon toothbrush (my preferred method), i finally started to see some lamination patterns in the usual typographical pattern. vague, but it was there. another hour spent applying vinegar with the toothbrush, but it seemed like this is about as bold as it will get, so i decided to neutralized the acid. after that was done, i ran hot tap water to wash off the baking soda. this is where it got weird. these unusual snake like lamination patterns started appearing all over the blade. the longer i applied hot water, the bolder the patterns got. it even overtook some of the typographical patterns, as in these darker lines were on top of the previous patterns. i've never seen this happen before. anyone ever had this experience? any explanation on what would cause these? one thing that is neat tho, it has this monochromatic scheme going; brass handle and baka-baka, darker brass collar, copper wire handle, and now these brown lines.
p.s.
for the record: i've handled moro blades for years, and i could honestly say that this is the very first time i've been "bitten" by a moro blade. weird.

[spiral]

Nice barung Spunjer!

Ive had the same expierience etching kukri, my conclusian was hot water & air promote an oxidisation that highlight the otherwise low contrast laminations, due to some layers or lamination lines of the bladel oxidising more rapidly than the others.

As a technique I think of it as controled oxidisation highlighting.

Guess it needs a heavy oil soaking afterwards.

Spiral

[ThePepperSkull]

silver kakatua.... *drool*

[Spunjer]

@spiral: thanks! I do have this habit of running a hot water test on these blades to see if they're laminated. When I did it initially, none of those patterns came out.
On your multi, did pattern stayed, or did it eventually fade? Yes, you're right: healthy dose of oil was applied right after...
@dave: It's brass, I'm pretty sure. It's just that it is the lighter shade type, not to mention I went against the grain and decided to clean it up. Of note is the weight of this beast: it's heavy, comparable in heft with kampilans.

[spiral]

Originally Posted by Spunjer

On your multi, did pattern stayed, or did it eventually fade? Yes, you're right: healthy dose of oil was applied right after...
.

It stays, but much cleaning fades it, I guess longer oxidisation leaves a more permant mark, a questian of getting the right balance I think?

Spiral