Identifying thread in bobbins

I am not sure why I didn't figure this out sooner!

I wonder if I once knew and forgot...  or if I just didn't care in the past...  I used to sew only clothing and household type items (pillows, curtains, etc).  

I work on AngelGowns, I quilt, I create doll clothes, I make bags and totes, and I make whatever bright and shiny thing that attracts my eye.  Some of these projects require a specific thread.

I have machines set up around my studio for each project, (it helps keeps my messy method of creating somewhat organized), and I have machines that use the same bobbins (Pfaff and Singer).

So the problem is:   How to know, once wound, if the thread on the bobbin is 100% cotton, 100% poly, or wrapped?   I empty my 50+ bobbins (I bet you think I am exaggerating :) and then wind them all at the same time on my bobbin winder.  I wind the colors I use most often, cottons for quilting, etc. and put them in their appropriate "station".   BUT!!!  sometimes, they stray. 

Personally, I find it inconvenient to keep a bobbin with a spool - I am not that OCD.  But even then, sometimes the spool loses its identifying end cap.  Some thread companies are using different types or colors of spools for different types of threads...  so this method works for spools, too... if needed.

I am remaining extremely hopeful that I am not the only one with this problem....  If I am the only one, I will be embarrassed and hope that no one points it out to me. :)

If I am not sure of the content of the bobbin and I need to use it, I am just lazy enough to force myself to guess that it is EXACTLY the type of thread I need at the moment.

Yes, I know....  I am "living in a fool's paradise".  (you get points for knowing the commercial that uses this)

So, the embarrassingly easy solution is that I am using a Sharpie to make a mark on the outside of the bobbin to color-coordinate to the type of thread. 

In my case,  the pink mark is quilting thread and the bobbins without color are poly thread.

The sharpie doesn't stain or color the thread but it does wear off eventually, so I just update when needed.

Of course, this method won't work for all bobbins but sometimes, the solution is something easy...  all it just takes a moment to think of it.