Titan Bitcoin (physical bitcoin) for sale

[mr.ebola]

Hi Everyone!
I have some physical bitcoins and I'm looking forward to sale some of them but I don't know how much should I ask for each.
For example, how much Btc should I ask for this coin:

2013 Titan One

Specifications
Diameter: 34mm (1.34″)
Weight: 12g (0.42 oz)
Material: Cupro-nickel alloy 230, also called “Goldine”
I purchased at:  1.329 BTC directly from https://www.titanbtc.com/product/titan-one/ some years ago.
I have the certificate and the coin is in 10/10 conditions.

I know these are collectibles and have more balances like: BTC+BCH+BSV, and much more forks.
I hope you guys can help me in this matter 

[Agrawas]

Best thing to do is an auction. But surely you should be able to get the similar price in BTC that you bought for..

[Carnomic]

Do these lose their luster or tarnish? Have any current pics?

[mr.ebola]

Best thing to do is an auction. But surely you should be able to get the similar price in BTC that you bought for..

Any suggestions of where can I  auction them ?
Thanks for all your answers!

[mr.ebola]

Do these lose their luster or tarnish? Have any current pics?

The titan bitcoins, look as new because they are in a capsule never open before.

I took this pictures yesterday:
Titan One Front: https://www.hackwise.mx/wp-content/uploads/2019/05/titanbtc.png
Titan One Back: https://www.hackwise.mx/wp-content/uploads/2019/05/coin.png
Certificate: https://www.hackwise.mx/wp-content/uploads/2019/05/WhatsApp-Image-2019-05-20-at-7.47.18-PM.png

If someone have some serious offers I'm willing to listening them, I receive bitcoin or ethereum for this coin