What is this frog made out of

[Peterhamm]

It’s nickel mounted but whatever the frog is made of is super easy scratched and they layered I think 6 layers across. Without light in it I thought it was horn but according to a few people I know they make horn frogs out of one piece. No chance it’s tortoiseshell right? When I think of tortoiseshell I always this of like a yellow brown mottled frog, not like this. The stick is alright, though nothing I’d really get excited about. 

[Mark Norfleet]

A bit hard to tell from photos, but probably tortoise shell, possibly buffalo horn.

[Peterhamm]

8 minutes ago, Mark Norfleet said:

A bit hard to tell from photos, but probably tortoise shell, possibly buffalo horn.

Why would they put tortoiseshell in nickel mounts on a probably not even pernambuco bow? It seems almost like putting lipstick on a pig 

[Mark Norfleet]

16 minutes ago, Peterhamm said:

Why would they put tortoiseshell in nickel mounts on a probably not even pernambuco bow? It seems almost like putting lipstick on a pig 

It’s possible that it’s plastic, but I don’t recall seeing a fake tortoise shell frog, fake ivory, but not tortoise shell.

Despite my best efforts, I still cannot read minds so I can’t reliably answer that question.

[Peterhamm]

1 minute ago, Mark Norfleet said:

It’s possible that it’s plastic, but I don’t recall seeing a fake tortoise shell frog, fake ivory, but not tortoise shell.

Despite my best efforts, I still cannot read minds so I can’t reliably answer that question.

I’ve seen em on Amazon but they usually don’t look like this. This just looks like ebony at a glance 

[Will Turner]

1 hour ago, Peterhamm said:

I’ve seen em on Amazon but they usually don’t look like this. This just looks like ebony at a glance 

I don't get a light through ebony when I test frogs, so while it appears as an ebony appearance, it's semi-translucent enough to have the light show as a red emission through the material (while quite opaque).

Perhaps it's a frankenbow.   The frog a higher quality tortoise shell that was slapped together with whatever random bits a bow restorer had a in bin?   Well, if the OP is also into restoration, perhaps save the frog for a finer bow, replacing the nickel bits with silver and put it on a better stick? 

[Jwillis]

Hit it with black light 

[Dorisch]

I havent seen any of the Grünkes use tortoise in ages. Must be an early RG?

 

[Jwillis]

Yes

[Peterhamm]

15 minutes ago, Will Turner said:

I don't get a light through ebony when I test frogs, so while it appears as an ebony appearance, it's semi-translucent enough to have the light show as a red emission through the material (while quite opaque).

Perhaps it's a frankenbow.   The frog a higher quality tortoise shell that was slapped together with whatever random bits a bow restorer had a in bin?   Well, if the OP is also into restoration, perhaps save the frog for a finer bow, replacing the nickel bits with silver and put it on a better stick? 

I honestly might do that. Here’s the stick it’s currently on. I have a fine penzel bow with a shattered frog that would probably do well with this 

[Peterhamm]

13 minutes ago, Jwillis said:

Hit it with black light 

I’m buying one today to do exactly that lol. Also since you own one how do you get them shiny again 

[Jwillis]

This one is exactly as I purchased and feel you shouldn’t take my advice on restoration. lol There are however videos about restoration of tortoiseshell online (tea caddy’s etc) and probably threads on maestronet regarding frogs. As well as real bow restorers who regularly post 

[Peterhamm]

27 minutes ago, Jwillis said:

This one is exactly as I purchased and feel you shouldn’t take my advice on restoration. lol There are however videos about restoration of tortoiseshell online (tea caddy’s etc) and probably threads on maestronet regarding frogs. As well as real bow restorers who regularly post 

Thank you lol gorgeous bow btw 

[Peterhamm]

I removed the slide and got a better surface to illuminate it from. Is it horn?

[Deo Lawson]

Looks like more like horn than tortoise to me, only because it has such a uniform colour. I haven't worked with much tortoise but if it were synthetic, the maker wouldn't bother laminating so many pieces. That's only done with natural materials that come in small pieces, like abalone.

Dyed epoxy would be the way to go for filling cracks and holes. 

[Peterhamm]

10 minutes ago, Deo Lawson said:

Looks like more like horn than tortoise to me, only because it has such a uniform colour. I haven't worked with much tortoise but if it were synthetic, the maker wouldn't bother laminating so many pieces. That's only done with natural materials that come in small pieces, like abalone.

Dyed epoxy would be the way to go for filling cracks and holes. 

I just wanna be on the safe side cuz I’ve heard border guards aren’t particularly nice to anything they think might be undocumented tortoiseshell

[Dorisch]

I have no Tortoiseshell bows, but the one with Ivory, for that I have a replacementfrog if I would need to get it over the border. The ivory one can savely sit at home in the vault. 
If your goal is to transport it, your own conclusions don't matter much. In this case I would get a certificate instead. 

[Peterhamm]

3 hours ago, Dorisch said:

I have no Tortoiseshell bows, but the one with Ivory, for that I have a replacementfrog if I would need to get it over the border. The ivory one can savely sit at home in the vault. 
If your goal is to transport it, your own conclusions don't matter much. In this case I would get a certificate instead. 

Thank you yall are great 

[Lisa Chamberlain]

14 hours ago, Peterhamm said:

Thank you yall are great 

I have real tortoiseshell that I can get pics of to compare if it would help. The hot needle test in a discrete place works - If it stinks to high heaven like burning hair -real. If it doesn’t stink too bad- horn. Fake tortoiseshell horn frogs can be found on EBay for comparison. “Horn Violin Frog”

[Peterhamm]

7 hours ago, Lisa Chamberlain said:

I have real tortoiseshell that I can get pics of to compare if it would help. The hot needle test in a discrete place works - If it stinks to high heaven like burning hair -real. If it doesn’t stink too bad- horn. Fake tortoiseshell horn frogs can be found on EBay for comparison. “Horn Violin Frog”

I can confirm it didn’t smell so good when I tried it lol. 

[lifestyle_nyc]

I have a viola bow with a tortoise shell frog. When were they banned? That would help me determine the age of the bow.

[David Burgess]

On 7/20/2026 at 11:46 AM, Mark Norfleet said:

A bit hard to tell from photos, but probably tortoise shell, possibly buffalo horn.

 

On 7/20/2026 at 11:56 AM, Peterhamm said:

Why would they put tortoiseshell in nickel mounts on a probably not even pernambuco bow? It seems almost like putting lipstick on a pig 

Maybe prettifying a pig is what they were trying to do.
The laminations (and one or two other things) suggest tortoise shell.  This wouldn't seem to be the most highly desired and transparent form of tortoise shell, so maybe they could get the cast-offs or rejects for cents on the dollar.

[Peterhamm]

13 minutes ago, David Burgess said:

 

Maybe prettifying a pig is what they were trying to do.
The laminations (and one or two other things) suggest tortoise shell.  This wouldn't seem to be the most highly desired and transparent form of tortoise shell, so maybe they could get the cast-offs or rejects for cents on the dollar.

That would honestly make sense. I figured it was some sort of French or German trade bow since they were always about doing things as cheap as possible while making it still look flashy for the catalogues 

[Peterhamm]

2 hours ago, lifestyle_nyc said:

I have a viola bow with a tortoise shell frog. When were they banned? That would help me determine the age of the bow.

1973 is when it was banned so there’s a pretty wide age range it could be