Rare Epididymite And “Ancylite” Crystals – Mont Saint - Hilaire
Item History & Price
| Reference Number: Avaluer:19975897 | Modified Item: No |
| Seller: LMB Minerals | Country/Region of Manufacture: Canada |
SuperbRare Epididymite and “Ancylite” crystals – Mont Saint-HilaireSize 40 x 25 x 15 mm. Weight: 0.6 oz(17 g). With MIN case 1.3 oz (37 g) Regarding epididymite, ancylite-(Ce), arfvedsonite, and thisspecimen:Epididymite is a rare mineral. While it is known from perhaps 80 localities, most ofthem in Norway and the Kolapeninsula, it is fairly common only at MSH and Mt.Malosa ( Malawi). MSH is not the TL for epididymite, but the best specimens are from here. It is usually foun...d as trillings or verycomplex arborescent twins – both of which can be quite attractive. But thecrystals on this specimen are relatively un-twinned, and some are even singlecrystals. Such crystals are unusual. The epididymite is associated with “ancylite”. This association is also veryunusual. Both ancylite-(Ce) and calcioancylite-(Ce) occur at MSH.According to the MSH rarity tables published in Lapis (July-Aug 2000), ancylite-(Ce)is fairly common and calcioancylite-(Ce) is moderately rare. Over theyears, various “rules of thumb” have been proposed that would permit one todistinguish these species visually. But a massive semi-quantitative EDS studyof hundreds of specimens by Tony Steede at the ROM showed that all but one ofthese rules is useless. The only rule that was found to have anyvalidity is that “ancylite” replacing other minerals is more likely tobe calcioancylite-(Ce) than ancylite-(Ce). It was also found that manyspecimens of “anycylite” have a borderline intermediate composition such thatonly detailed chemical analysis (e.g. WDS) could be definitive. (Acomprehensive book on the minerals of MSH will soon be available. Perhaps itwill shed new light on this issue.) This specimen was sold as “calcioancylite-(Ce)” based on one of the – nowdebunked – “rules of thumb”. But these crystals do not appear to be replacinganything, so there is nothing to indicate that they are more likely to becalcioancylite-(Ce) than ancylite-(Ce). They might – or might not - becalcioancylite-(Ce). If you are lucky, qualitative EDS might be definitiveenough. But it is more likely that qualitative EDS will not suffice. I know that collectors prefer definitive labels. But labels that say“calcioancylite-(Ce)” are usually just wishful thinking. Caveat emptor. (If alabel says “ancylite-(Ce)”, it is more likely to be correct simply because, atMSH, ancylite-(Ce) is considerably more common than calcioancylite-(Ce) – butthat’s not a guarantee.) In any case, the “ancylite” on this specimen is very attractive.In addition, there are small but extremely sharp and attractive crystals ofarfvedsonite, as well as well-formed crystals of yellow calcite. There are alsoabundant tiny white needles which are probably fluorapatite or “carbonate richfluorapatite”, but they were not analyzed and other things are possible. Regarding the photos: The firstthree photos (FOV 4.4 x 5.9 mm) show the largest group of epididymite crystals on the specimen. If you can fuse the stereopair in the third photo, you will see that this a stack of three crystals, thelargest of which is 3.6 mm long. However, I think that these are just threesingle crystals of epididymite, perhaps in parallel growth, rather than themore common penetration trillings. (If you can’t fuse the stereo pair, tryflipping back and forth between the first two photos.)The nexttwo photos (FOV 4.0 x 6.5 mm) show two more epididymite crystals, the largest ca 2.5 mm in diameter. There aresome smaller epididymite crystalsbehind these, but I don’t think that any of these crystals is a twin. Thepinkish crystals are “ancylite”, theyellowish stuff is calcite. In thiscase, the second photo is a stereo pair.The nexttwo photos (FOV 3.7 x 2.2 mm) show the largest “ancylite flowers” on the specimen. The “petals” are ca 0.9 mm long.Under a scope, these crystals have a very beautiful, pale pink, translucencythat I wasn’t really able to capture in the photos. Stereo (second photo)helps, but still falls short of “reality”.The nexttwo photos (FOV 4.0 x 5.5 mm) show several smaller “ancylite”groups to 0.9 mm in diameter. These “ancylite flowers” are very pretty undera scope. There is also a single epididymite crystal 1.4 mm in diameter, andwell formed yellow calcite crystals with selectively frosted faces. The longestedge on the calcite is 1.5 mm. The second photo is again a stereo pair.As alreadymentioned, the specimen also host some small, but very sharply formed, crystalsof black arfvedsonite, and anabundance of small white to yellowish “needles”. The “needles” are probably fluorapatite (or the variety carbonate fluorapatite), but thematerial was not tested in any way, and there are other possibilities (such asa burbankite group mineral). The next two photos (FOV 3.3 x 2.4 mm) show anexample of both the arfvedsonite andthe (possible) fluorapatite. Thelongest edge on the arfvedsonite is1.1 mm. The second photo is a stereo pair.There aresome larger arfvedsonite crystals onthe specimen, but they are either not very interesting or else are even moreencrusted by the tiny needles of “fluorapatite”.
In the full-view photo, the pearly white crystals are epididymite, the pinkishstuff is “ancylite”, the yellow stuff is calcite, the small black crystals arearfvedsonite, and the fuzzy white patches are (probably) fluorapatite. The backand sides of the specimen are somewhat similar but the crystals are not asnice. The specimen appears to have formed as a sort of stalactite or stalagmitein a (pegmatite?) cavity.Regarding shipping etc:Single item shipping weight 4.1 oz(116g). Please use the postage calculator to estimate shipping costs toyour destination. Note that eBay and PayPal sellercharges are based on the total price - including postage and packingcosts! This adds about $2.25 to the cost of shipping to most non-USAdestinations. For small orders, I must pass most of this extra cost on to thebuyer. It is included in the shipping estimate via a “handling” charge. Forlarger orders, I generally give discounted postage. If you want to save on postage by combiningitems from this or other auctions you must wait for my invoice. I willautomatically combine items if I can. For shipments outsidethe USA, up to a total weight< 8 oz (225g), this can be combined with items from this or otherauctions for the same postage. Within the USA, the net shippingcost for total weights up to 13 oz ranges from $5.10 to $7.00 (including $0.75for packing). Above 13 oz, I will use "own box" PriorityMail. The rate, including packing and eBay/PayPal fees varies bydestination from $9 to $11.I only ship standard rate to the USA (including Puerto Rico etc), Canada, Mexico, Europe (excluding Russian Federation), Australia, New Zealand, China, Hong Kong, Taiwan, Japan, South Korea, and Singapore. All other destinations, you must inquire before bidding. I will try to work with you, but insurance andfull tracking may be required. If you experience a lost package, you may bebarred from further bidding. In my experience, there has been only one lostpackage and two damaged packages out of several hundred sent. I have done my best to provide accurate IDs. Ifyou are not convinced, don't bid. You are always welcome to ask for moreinformation. But this is not an "approval" service for peoplewho want to learn how to identify rare minerals or mineralogists looking forstudy material. Returns are only accepted for items over $50, and thebuyer is responsible for return postage. Shipping charges assessed for packagesreturned due to non-payment of any customs/VAT fees assessed by the destinationcountry are also the buyer's responsibility. This should not be a"real" issue. Out of several hundred packages sent, I have had onlyone return.
In the full-view photo, the pearly white crystals are epididymite, the pinkishstuff is “ancylite”, the yellow stuff is calcite, the small black crystals arearfvedsonite, and the fuzzy white patches are (probably) fluorapatite. The backand sides of the specimen are somewhat similar but the crystals are not asnice. The specimen appears to have formed as a sort of stalactite or stalagmitein a (pegmatite?) cavity.Regarding shipping etc:Single item shipping weight 4.1 oz(116g). Please use the postage calculator to estimate shipping costs toyour destination. Note that eBay and PayPal sellercharges are based on the total price - including postage and packingcosts! This adds about $2.25 to the cost of shipping to most non-USAdestinations. For small orders, I must pass most of this extra cost on to thebuyer. It is included in the shipping estimate via a “handling” charge. Forlarger orders, I generally give discounted postage. If you want to save on postage by combiningitems from this or other auctions you must wait for my invoice. I willautomatically combine items if I can. For shipments outsidethe USA, up to a total weight< 8 oz (225g), this can be combined with items from this or otherauctions for the same postage. Within the USA, the net shippingcost for total weights up to 13 oz ranges from $5.10 to $7.00 (including $0.75for packing). Above 13 oz, I will use "own box" PriorityMail. The rate, including packing and eBay/PayPal fees varies bydestination from $9 to $11.I only ship standard rate to the USA (including Puerto Rico etc), Canada, Mexico, Europe (excluding Russian Federation), Australia, New Zealand, China, Hong Kong, Taiwan, Japan, South Korea, and Singapore. All other destinations, you must inquire before bidding. I will try to work with you, but insurance andfull tracking may be required. If you experience a lost package, you may bebarred from further bidding. In my experience, there has been only one lostpackage and two damaged packages out of several hundred sent. I have done my best to provide accurate IDs. Ifyou are not convinced, don't bid. You are always welcome to ask for moreinformation. But this is not an "approval" service for peoplewho want to learn how to identify rare minerals or mineralogists looking forstudy material. Returns are only accepted for items over $50, and thebuyer is responsible for return postage. Shipping charges assessed for packagesreturned due to non-payment of any customs/VAT fees assessed by the destinationcountry are also the buyer's responsibility. This should not be a"real" issue. Out of several hundred packages sent, I have had onlyone return.
