Rare earth elements (REEs) have been the mystery metals of the mining world for years. Now, suddenly, everyone’s heard about them.

The base metals were all in the red again on Friday. Copper dropped in the pre-dawn hours and, though it rallied through the New York session, never got back to even, finishing at $3.4242/lb., down more than 5 cents.

The base metals were mostly in the black on Friday. Copper started up in the pre-dawn hours and kept pushing higher during most of the trading day, finishing barely off its intraday high at $3.8965/lb., up 5 cents.

The base metals were mixed on Thursday. Copper sank during the pre-dawn hours but took off during the first hour of New York trading, before easing later in the day and finishing at $3.8466/lb., up 2¼ cents.

The base metals were mixed on Friday. Copper was flat until the late morning, then shot upward, peaking around noon before flattening out after that to finish at $3.6656/lb., up 5 cents.

The base metals were mostly in the red on Thursday. Copper declined from the pre-dawn hours through to mid-morning, then rallied to finish at $3.6157/lb., down just more than 2 1/3 cents. Nickel prolonged its recent resurgence, rising steadily to push back over the $11 mark, closing at $11.0873/lb., up 61 cents.

The base metals were mixed again on Wednesday. Copper sagged through the pre-dawn hours, but recaptured the lost ground during the New York session, finishing at $3.6395/lb., up a penny and a half.

The base metals were mostly higher on Friday. Copper rose during the pre-dawn hours, peaking at $3.73 near the New York open, then slid for most of the rest of the day, finishing at $3.6965/lb., up 9 cents.

The base metals were mixed again on Thursday. Copper sank during the pre-dawn hours and fought its way back during the New York session though it fell short of positive territory at $3.6068/lb., down more than a penny and a third.

Gold didn’t do much of anything on Wednesday until well into the trading day in London.