Dama Ben Netinah and The Stones of the High Priest's Breast Plate

There are a series of names given in the Torah for the stones of the breastplate, but matching these very rare Hebrew words exactly to precise gems, or even precise gem colours has always been allusive.

I'm doing something on the story of Dama Ben Netina who, in the Bavli, refuses to wake up his father when the Rabbis come to buy jewels for the breastplate from him - dad's asleep on a pillow, and the key to the is under the pillow. The story continues that Dama gets a reward of having a red heifer born into his flock. In the Yerushalmi, it's only one stone the ישפה stone for the breastplate corresponding to the tribe of Benjamin. 

The Septuagint translates ישפה as iaspis -  a green jasper (a rare form). Other Targumim and commentaries suggest ישפה is a yellow hyacinth, a green emerald and a red ruby. Bmidbar Rabba (2.7) suggests that it was multicoloured.

But if the birth of the heifer is a like-begats-like or midah-keneged-midah reward for Dama's piety, then, surely, it makes sense that the stone was red. ישפה and iaspis - are roughly cognates of jasper - and the most common form of jasper is red. As geologists will know far better than I, jasper is a kind of quartz and is coloured as a result of metal 'impurities' present during its formation. So actually, you can get jasper in green, or red or even (thank you Bmidbar Rabba) multicoloured.

Actually, the red-word play is all over the Talmudic story. This is from @nachman levine https://www.academia.edu/487232/Dama_ben_Netina

In the Bavli’s wordplay in several places a Parah Adumah’s (אדומה) price (damehah) is very high (damehah yekarin, דדמיה יקרין). In the Deut. Rabah and Pesikta versions, the stones’ price (dameha) rises to ten thousand gold coins (והעלו דמיה) but Dama (דמה) won’t exploit his father’s honor beyond the original price (damim harishonim, בדמים הראשונים), to merit a Parah Adumah (פרה אדומה) worth ten thousand coins.
In the Yerushalmi, as Dama (דמה) goes up and finds his father sleeping (דמיך, damich), the sages raise the price each time he comes down (סליק בעי מייתה להו ואשכח אבוה דמיך, אסקוניה למאתים, אסקוניה לאלף) so that the rising market price is directly tied to his fulfilling the commandment of honouring his father. Honoring his father’s sleeping (דמיך, damich) raises the price (דמים, damim) later redeemed (para`) by the “parah//adumah” in place of the “peritin//damim” (pennies//price) Dama declined.

So - evidence, from a story that is of temple-period that ישפה is indeed jasper, and in this case red jasper.