flinty

Resembling or containing flint; hard like flint.

• It was late at night and frosty; high above them on the hills the cloppety clop, cloppety clop of a horse's hooves picking their way on the flinty stone track died away in the distance.

Siliceous (including basanite).

• flinty rock
• flinty slate

Showing a lack of emotion.figuratively

• Public opinion has turned flintier in recent years on welfare spending.
• While the texture of his playing was often flinty, his licks and leads were flush with feeling.

Having a taste characteristic of certain white wines, especially Chablis, supposed to evoke the sensation of flint striking steel.

• Wines can be described with words like cigar box and “pencil lead,” or flinty or with hints of sandalwood — oenophiles can veer into what many might deem pretentiousness pretty quick.